For Perf. Reasons don't use Exception

src/AddIns/DisplayBindings/WpfDesign/WpfDesign.XamlDom/Project/CollectionSupport.cs

@@ -105,13 +105,22 @@ namespace ICSharpCode.WpfDesign.XamlDom
 			/// <summary>
 		/// Adds a value at the specified index in the collection.
 		/// </summary>
-		public static void Insert(Type collectionType, object collectionInstance, XamlPropertyValue newElement, int index)
+		public static bool Insert(Type collectionType, object collectionInstance, XamlPropertyValue newElement, int index)
 		{
+			var mth = collectionType.GetMethod("Insert", BindingFlags.Public | BindingFlags.Instance,
+			                         null, CallingConventions.Any, new Type[]{ typeof(int), typeof(object) }, null);
+			
+			if (mth != null) {
 				collectionType.InvokeMember(
 					"Insert", BindingFlags.Public | BindingFlags.InvokeMethod | BindingFlags.Instance,
 					null, collectionInstance,
 					new object[] { index, newElement.GetValueFor(null) },
 					CultureInfo.InvariantCulture);
+				
+				return true;
+			}
+			
+			return false;
 		}
 		
 		/// <summary>
@@ -121,7 +130,7 @@ namespace ICSharpCode.WpfDesign.XamlDom
 		internal static bool TryInsert(Type collectionType, object collectionInstance, XamlPropertyValue newElement, int index)
 		{
 			try {
-				Insert(collectionType, collectionInstance, newElement, index);
+				return Insert(collectionType, collectionInstance, newElement, index);
 			} catch (MissingMethodException) {
 				return false;
 			}