Index: Riskeer/Common/src/Riskeer.Common.Forms/ChangeHandlers/ClearIllustrationPointsOfCalculationChangeHandlerBase.cs
===================================================================
diff -u -r43cf20905f2808ce0ac0b0408d8cf0017bd9efca -ra68f144ae66e3c768759bf16cc26dfca2e2aed49
--- Riskeer/Common/src/Riskeer.Common.Forms/ChangeHandlers/ClearIllustrationPointsOfCalculationChangeHandlerBase.cs	(.../ClearIllustrationPointsOfCalculationChangeHandlerBase.cs)	(revision 43cf20905f2808ce0ac0b0408d8cf0017bd9efca)
+++ Riskeer/Common/src/Riskeer.Common.Forms/ChangeHandlers/ClearIllustrationPointsOfCalculationChangeHandlerBase.cs	(.../ClearIllustrationPointsOfCalculationChangeHandlerBase.cs)	(revision a68f144ae66e3c768759bf16cc26dfca2e2aed49)
@@ -27,7 +27,7 @@
 namespace Riskeer.Common.Forms.ChangeHandlers
 {
     /// <summary>
-    /// Base class for handling objects when clearing illustration points from a calculation.
+    /// Base class for handling clearing illustration points from a calculation.
     /// </summary>
     /// <typeparam name="TCalculation">The type of calculation.</typeparam>
     public abstract class ClearIllustrationPointsOfCalculationChangeHandlerBase<TCalculation> : IClearIllustrationPointsOfCalculationChangeHandler
@@ -37,10 +37,10 @@
         protected TCalculation Calculation;
 
         /// <summary>
-        /// Creates a new instance of <see cref="ClearIllustrationPointsOfCalculationChangeHandlerBase{T}"/>.
+        /// Creates a new instance of <see cref="ClearIllustrationPointsOfCalculationChangeHandlerBase{TCalculation}"/>.
         /// </summary>
-        /// <param name="inquiryHelper">Object responsible for inquiring the required data.</param>
-        /// <param name="calculation">The calculation for which the illustration points should be cleared for.</param>
+        /// <param name="inquiryHelper">Object responsible for inquiring confirmation.</param>
+        /// <param name="calculation">The calculation to clear the illustration points for.</param>
         /// <exception cref="ArgumentNullException">Thrown when any argument is <c>null</c>.</exception>
         protected ClearIllustrationPointsOfCalculationChangeHandlerBase(IInquiryHelper inquiryHelper,
                                                                         TCalculation calculation)
Index: Riskeer/Common/src/Riskeer.Common.Forms/ChangeHandlers/ClearIllustrationPointsOfCalculationCollectionChangeHandlerBase.cs
===================================================================
diff -u -r6d18571198270d2bce752be57493a447fee10680 -ra68f144ae66e3c768759bf16cc26dfca2e2aed49
--- Riskeer/Common/src/Riskeer.Common.Forms/ChangeHandlers/ClearIllustrationPointsOfCalculationCollectionChangeHandlerBase.cs	(.../ClearIllustrationPointsOfCalculationCollectionChangeHandlerBase.cs)	(revision 6d18571198270d2bce752be57493a447fee10680)
+++ Riskeer/Common/src/Riskeer.Common.Forms/ChangeHandlers/ClearIllustrationPointsOfCalculationCollectionChangeHandlerBase.cs	(.../ClearIllustrationPointsOfCalculationCollectionChangeHandlerBase.cs)	(revision a68f144ae66e3c768759bf16cc26dfca2e2aed49)
@@ -27,7 +27,7 @@
 namespace Riskeer.Common.Forms.ChangeHandlers
 {
     /// <summary>
-    /// Base class for handling objects when clearing illustration points from collections of calculations.
+    /// Base class for handling clearing illustration points from collections of calculations.
     /// </summary>
     public abstract class ClearIllustrationPointsOfCalculationCollectionChangeHandlerBase 
         : IClearIllustrationPointsOfCalculationCollectionChangeHandler
@@ -38,7 +38,7 @@
         /// <summary>
         /// Creates a new instance of <see cref="ClearIllustrationPointsOfCalculationCollectionChangeHandlerBase"/>.
         /// </summary>
-        /// <param name="inquiryHelper">Object responsible for inquiring the required data.</param>
+        /// <param name="inquiryHelper">Object responsible for inquiring confirmation.</param>
         /// <param name="inquiry">The inquiry that should be displayed when inquiring whether the illustration points
         /// should be cleared.</param>
         /// <exception cref="ArgumentNullException">Thrown when any parameter is <c>null</c>.</exception>
Index: Riskeer/Common/src/Riskeer.Common.Forms/ChangeHandlers/ClearIllustrationPointsOfHydraulicBoundaryLocationCalculationCollectionChangeHandler.cs
===================================================================
diff -u -r32e70d7a1e20d6b63a5d3d7fb2593ed77c25800a -ra68f144ae66e3c768759bf16cc26dfca2e2aed49
--- Riskeer/Common/src/Riskeer.Common.Forms/ChangeHandlers/ClearIllustrationPointsOfHydraulicBoundaryLocationCalculationCollectionChangeHandler.cs	(.../ClearIllustrationPointsOfHydraulicBoundaryLocationCalculationCollectionChangeHandler.cs)	(revision 32e70d7a1e20d6b63a5d3d7fb2593ed77c25800a)
+++ Riskeer/Common/src/Riskeer.Common.Forms/ChangeHandlers/ClearIllustrationPointsOfHydraulicBoundaryLocationCalculationCollectionChangeHandler.cs	(.../ClearIllustrationPointsOfHydraulicBoundaryLocationCalculationCollectionChangeHandler.cs)	(revision a68f144ae66e3c768759bf16cc26dfca2e2aed49)
@@ -28,7 +28,7 @@
 namespace Riskeer.Common.Forms.ChangeHandlers
 {
     /// <summary>
-    /// Class for handling collections of hydraulic boundary location calculations when its illustration point results need to be cleared.
+    /// Class for handling clearing the illustration points results from a collection of hydraulic boundary location calculations.
     /// </summary>
     public class ClearIllustrationPointsOfHydraulicBoundaryLocationCalculationCollectionChangeHandler 
         : ClearIllustrationPointsOfCalculationCollectionChangeHandlerBase
@@ -38,7 +38,7 @@
         /// <summary>
         /// Creates a new instance of <see cref="ClearIllustrationPointsOfHydraulicBoundaryLocationCalculationCollectionChangeHandler"/>.
         /// </summary>
-        /// <param name="inquiryHelper">Object responsible for inquiring the required data.</param>
+        /// <param name="inquiryHelper">Object responsible for inquiring confirmation.</param>
         /// <param name="collectionDescription">The description of the collection in which the illustration points results belong to.</param>
         /// <param name="clearIllustrationPointsFunc">The function to clear the illustration point results.</param>
         /// <exception cref="ArgumentNullException">Thrown when any parameter is <c>null</c>.</exception>
Index: Riskeer/Common/src/Riskeer.Common.Forms/ChangeHandlers/ClearIllustrationPointsOfStructureCalculationCollectionChangeHandler.cs
===================================================================
diff -u -rd4fb475f3f6e36b919118b6c1ed100ce45dbf356 -ra68f144ae66e3c768759bf16cc26dfca2e2aed49
--- Riskeer/Common/src/Riskeer.Common.Forms/ChangeHandlers/ClearIllustrationPointsOfStructureCalculationCollectionChangeHandler.cs	(.../ClearIllustrationPointsOfStructureCalculationCollectionChangeHandler.cs)	(revision d4fb475f3f6e36b919118b6c1ed100ce45dbf356)
+++ Riskeer/Common/src/Riskeer.Common.Forms/ChangeHandlers/ClearIllustrationPointsOfStructureCalculationCollectionChangeHandler.cs	(.../ClearIllustrationPointsOfStructureCalculationCollectionChangeHandler.cs)	(revision a68f144ae66e3c768759bf16cc26dfca2e2aed49)
@@ -30,7 +30,7 @@
 namespace Riskeer.Common.Forms.ChangeHandlers
 {
     /// <summary>
-    /// Class for handling a collection of structure calculations when its illustration points need to be cleared.
+    /// Class for handling clearing illustration points from a collection of structure calculations.
     /// </summary>
     public class ClearIllustrationPointsOfStructureCalculationCollectionChangeHandler
         : ClearIllustrationPointsOfCalculationCollectionChangeHandlerBase
@@ -40,7 +40,7 @@
         /// <summary>
         /// Creates a new instance of <see cref="ClearIllustrationPointsOfStructureCalculationCollectionChangeHandler"/>.
         /// </summary>
-        /// <param name="inquiryHelper">Object responsible for inquiring the required data.</param>
+        /// <param name="inquiryHelper">Object responsible for inquiring confirmation.</param>
         /// <param name="calculations">The calculations for which the illustration points should be cleared for.</param>
         /// <exception cref="ArgumentNullException">Thrown when any parameter is <c>null</c>.</exception>
         public ClearIllustrationPointsOfStructureCalculationCollectionChangeHandler(IInquiryHelper inquiryHelper,
Index: Riskeer/Common/src/Riskeer.Common.Forms/ChangeHandlers/ClearIllustrationPointsOfStructuresCalculationHandler.cs
===================================================================
diff -u -r3a3098e608408b9b09e7b2511f0895ffe5b63bc1 -ra68f144ae66e3c768759bf16cc26dfca2e2aed49
--- Riskeer/Common/src/Riskeer.Common.Forms/ChangeHandlers/ClearIllustrationPointsOfStructuresCalculationHandler.cs	(.../ClearIllustrationPointsOfStructuresCalculationHandler.cs)	(revision 3a3098e608408b9b09e7b2511f0895ffe5b63bc1)
+++ Riskeer/Common/src/Riskeer.Common.Forms/ChangeHandlers/ClearIllustrationPointsOfStructuresCalculationHandler.cs	(.../ClearIllustrationPointsOfStructuresCalculationHandler.cs)	(revision a68f144ae66e3c768759bf16cc26dfca2e2aed49)
@@ -26,21 +26,21 @@
 namespace Riskeer.Common.Forms.ChangeHandlers
 {
     /// <summary>
-    /// Class for handling clearing illustration point results of a single structures calculation.
+    /// Class for handling clearing illustration point results from a structures calculation.
     /// </summary>
     /// <typeparam name="TStructureInput">Object type of the structure calculation input.</typeparam>
     public class ClearIllustrationPointsOfStructuresCalculationHandler<TStructureInput>
-        : ClearIllustrationPointsOfCalculationChangeHandlerBase<StructuresCalculation<TStructureInput>>
+        : ClearIllustrationPointsOfCalculationChangeHandlerBase<IStructuresCalculation>
         where TStructureInput : IStructuresCalculationInput, new()
     {
         /// <summary>
         /// Creates a new instance of <see cref="ClearIllustrationPointsOfStructuresCalculationHandler{TStructureInput}"/>.
         /// </summary>
-        /// <param name="inquiryHelper">Object responsible for inquiring the required data.</param>
-        /// <param name="calculation">The calculation for which the illustration points should be cleared for.</param>
+        /// <param name="inquiryHelper">Object responsible for inquiring confirmation.</param>
+        /// <param name="calculation">The calculation to clear the illustration points for.</param>
         /// <exception cref="ArgumentNullException">Thrown when any parameter is <c>null</c>.</exception>
         public ClearIllustrationPointsOfStructuresCalculationHandler(IInquiryHelper inquiryHelper,
-                                                                     StructuresCalculation<TStructureInput> calculation)
+                                                                     IStructuresCalculation calculation)
             : base(inquiryHelper, calculation) {}
 
         public override bool ClearIllustrationPoints()
Index: Riskeer/Common/test/Riskeer.Common.Forms.Test/ChangeHandlers/ClearIllustrationPointsOfStructuresCalculationHandlerTest.cs
===================================================================
diff -u -r3a3098e608408b9b09e7b2511f0895ffe5b63bc1 -ra68f144ae66e3c768759bf16cc26dfca2e2aed49
--- Riskeer/Common/test/Riskeer.Common.Forms.Test/ChangeHandlers/ClearIllustrationPointsOfStructuresCalculationHandlerTest.cs	(.../ClearIllustrationPointsOfStructuresCalculationHandlerTest.cs)	(revision 3a3098e608408b9b09e7b2511f0895ffe5b63bc1)
+++ Riskeer/Common/test/Riskeer.Common.Forms.Test/ChangeHandlers/ClearIllustrationPointsOfStructuresCalculationHandlerTest.cs	(.../ClearIllustrationPointsOfStructuresCalculationHandlerTest.cs)	(revision a68f144ae66e3c768759bf16cc26dfca2e2aed49)
@@ -19,9 +19,7 @@
 // Stichting Deltares and remain full property of Stichting Deltares at all times.
 // All rights reserved.
 
-using System;
 using System.Collections.Generic;
-using Core.Common.Base;
 using Core.Common.Gui;
 using NUnit.Framework;
 using Rhino.Mocks;
@@ -56,8 +54,7 @@
         [Test]
         [TestCaseSource(nameof(GetCalculationConfigurations))]
         public void ClearIllustrationPoints_WithVariousCalculationConfigurations_ClearsIllustrationPointsAndReturnsExpectedResult(
-            TestStructuresCalculation calculation,
-            bool expectedResult)
+            TestStructuresCalculation calculation, bool expectedResult)
         {
             // Setup
             var mocks = new MockRepository();
@@ -75,10 +72,8 @@
             Assert.AreEqual(expectedResult, isCalculationAffected);
             Assert.AreEqual(hasOutput, calculation.HasOutput);
 
-            if (hasOutput)
-            {
-                Assert.IsFalse(calculation.Output.HasGeneralResult);
-            }
+            Assert.IsNull(calculation.Output?.GeneralResult);
+            mocks.VerifyAll();
         }
 
         private static IEnumerable<TestCaseData> GetCalculationConfigurations()
Index: Riskeer/GrassCoverErosionInwards/src/Riskeer.GrassCoverErosionInwards.Forms/ChangeHandlers/ClearIllustrationPointsOfGrassCoverErosionInwardsCalculationChangeHandler.cs
===================================================================
diff -u -r6aa5efc255fee38e43af3e74e0c9be6f006db2ba -ra68f144ae66e3c768759bf16cc26dfca2e2aed49
--- Riskeer/GrassCoverErosionInwards/src/Riskeer.GrassCoverErosionInwards.Forms/ChangeHandlers/ClearIllustrationPointsOfGrassCoverErosionInwardsCalculationChangeHandler.cs	(.../ClearIllustrationPointsOfGrassCoverErosionInwardsCalculationChangeHandler.cs)	(revision 6aa5efc255fee38e43af3e74e0c9be6f006db2ba)
+++ Riskeer/GrassCoverErosionInwards/src/Riskeer.GrassCoverErosionInwards.Forms/ChangeHandlers/ClearIllustrationPointsOfGrassCoverErosionInwardsCalculationChangeHandler.cs	(.../ClearIllustrationPointsOfGrassCoverErosionInwardsCalculationChangeHandler.cs)	(revision a68f144ae66e3c768759bf16cc26dfca2e2aed49)
@@ -28,16 +28,16 @@
 namespace Riskeer.GrassCoverErosionInwards.Forms.ChangeHandlers
 {
     /// <summary>
-    /// Class for handling clearing illustration point results of a single grass cover erosion inwards calculation.
+    /// Class for handling clearing illustration point results from a grass cover erosion inwards calculation.
     /// </summary>
     public class ClearIllustrationPointsOfGrassCoverErosionInwardsCalculationChangeHandler
         : ClearIllustrationPointsOfCalculationChangeHandlerBase<GrassCoverErosionInwardsCalculation>
     {
         /// <summary>
         /// Creates a new instance of <see cref="ClearIllustrationPointsOfGrassCoverErosionInwardsCalculationChangeHandler"/>.
         /// </summary>
-        /// <param name="inquiryHelper">Object responsible for inquiring the required data.</param>
-        /// <param name="calculation">The calculation for which the illustration points should be cleared for.</param>
+        /// <param name="inquiryHelper">Object responsible for inquiring confirmation.</param>
+        /// <param name="calculation">The calculation to clear the illustration points for.</param>
         /// <exception cref="ArgumentNullException">Thrown when any argument is <c>null</c>.</exception>
         public ClearIllustrationPointsOfGrassCoverErosionInwardsCalculationChangeHandler(IInquiryHelper inquiryHelper,
                                                                                          GrassCoverErosionInwardsCalculation calculation)
Index: Riskeer/GrassCoverErosionInwards/src/Riskeer.GrassCoverErosionInwards.Forms/ChangeHandlers/ClearIllustrationPointsOfGrassCoverErosionInwardsCalculationCollectionChangeHandler.cs
===================================================================
diff -u -rbb831b80442c0389546ce12572e24c795e0f6df6 -ra68f144ae66e3c768759bf16cc26dfca2e2aed49
--- Riskeer/GrassCoverErosionInwards/src/Riskeer.GrassCoverErosionInwards.Forms/ChangeHandlers/ClearIllustrationPointsOfGrassCoverErosionInwardsCalculationCollectionChangeHandler.cs	(.../ClearIllustrationPointsOfGrassCoverErosionInwardsCalculationCollectionChangeHandler.cs)	(revision bb831b80442c0389546ce12572e24c795e0f6df6)
+++ Riskeer/GrassCoverErosionInwards/src/Riskeer.GrassCoverErosionInwards.Forms/ChangeHandlers/ClearIllustrationPointsOfGrassCoverErosionInwardsCalculationCollectionChangeHandler.cs	(.../ClearIllustrationPointsOfGrassCoverErosionInwardsCalculationCollectionChangeHandler.cs)	(revision a68f144ae66e3c768759bf16cc26dfca2e2aed49)
@@ -41,7 +41,7 @@
         /// <summary>
         /// Creates a new instance of <see cref="ClearIllustrationPointsOfGrassCoverErosionInwardsCalculationCollectionChangeHandler"/>.
         /// </summary>
-        /// <param name="inquiryHelper">Object responsible for inquiring the required data.</param>
+        /// <param name="inquiryHelper">Object responsible for inquiring confirmation.</param>
         /// <param name="calculations">The calculations for which the illustration points should be cleared for.</param>
         /// <exception cref="System.ArgumentNullException">Thrown when any parameter is <c>null</c>.</exception>
         public ClearIllustrationPointsOfGrassCoverErosionInwardsCalculationCollectionChangeHandler(IInquiryHelper inquiryHelper,