diff --git a/src/AddIns/Debugger/Debugger.AddIn/Visualizers/Graph/Layout/GraphDiff.cs b/src/AddIns/Debugger/Debugger.AddIn/Visualizers/Graph/Layout/GraphDiff.cs
index cac03f8138..3e1747a66a 100644
--- a/src/AddIns/Debugger/Debugger.AddIn/Visualizers/Graph/Layout/GraphDiff.cs
+++ b/src/AddIns/Debugger/Debugger.AddIn/Visualizers/Graph/Layout/GraphDiff.cs
@@ -9,7 +9,7 @@ using Debugger.AddIn.Visualizers.Utils;
 namespace Debugger.AddIn.Visualizers.Graph.Layout
 {
 	/// <summary>
-	/// Describes changes between 2 <see cref="PositionedGraph"/>s.
+	/// Describes changes which occured between 2 <see cref="PositionedGraph"/>s.
 	/// </summary>
 	public class GraphDiff
 	{
@@ -35,8 +35,8 @@ namespace Debugger.AddIn.Visualizers.Graph.Layout
 		}
 		
 		/// <summary>
-		/// Nodes in the old graph that were chaged.
-		/// These have matching new nodes, which can be obtained by <see cref="GetMatchingNewNode"/>.
+		/// Nodes in the old graph that are present also in the new graph (they represent the same debuggee instance).
+		/// The matching new nodes can be obtained by <see cref="GetMatchingNewNode"/>.
 		/// </summary>
 		public IList<PositionedNode> ChangedNodes
 		{
@@ -63,17 +63,5 @@ namespace Debugger.AddIn.Visualizers.Graph.Layout
 			matching[matchFrom] = matchTo;
 			changedNodes.Add(matchFrom);
 		}
-		
-		public GraphDiff()
-		{
-			
-		}
-		
-		/*public void MakeReadOnly()
-		{
-			addedNodes = ((List<PositionedNode>)addedNodes).AsReadOnly();
-			deletedNodes = ((List<PositionedNode>)deletedNodes).AsReadOnly();
-			changedNodes = ((List<PositionedNode>)changedNodes).AsReadOnly();
-		}*/
 	}
 }
diff --git a/src/AddIns/Debugger/Debugger.AddIn/Visualizers/Graph/Layout/GraphMatcher.cs b/src/AddIns/Debugger/Debugger.AddIn/Visualizers/Graph/Layout/GraphMatcher.cs
index dc241f67b8..3a4c5e0ff3 100644
--- a/src/AddIns/Debugger/Debugger.AddIn/Visualizers/Graph/Layout/GraphMatcher.cs
+++ b/src/AddIns/Debugger/Debugger.AddIn/Visualizers/Graph/Layout/GraphMatcher.cs
@@ -8,92 +8,76 @@ using Debugger.AddIn.Visualizers.Utils;
 namespace Debugger.AddIn.Visualizers.Graph.Layout
 {
 	/// <summary>
-	/// Calculates diff of 2 <see cref="PositionedGraph"/>s.
+	/// Calculates diff between 2 <see cref="PositionedGraph"/>s.
 	/// </summary>
 	public class GraphMatcher
 	{
-		public GraphMatcher()
-		{
-		}
-		
+		/// <summary>
+		/// Calculates diff between 2 <see cref="PositionedGraph"/>s. 
+		/// The <see cref="GraphDiff"/> describes a matching between nodes in the graphs, added and removed nodes.
+		/// </summary>
 		public GraphDiff MatchGraphs(PositionedGraph oldGraph, PositionedGraph newGraph)
 		{
-			if (oldGraph == null)
-			{
-				if (newGraph == null)
-				{
+			if (oldGraph == null) {
+				if (newGraph == null) {
 					return new GraphDiff();
-				}
-				else
-				{
+				} else {
 					GraphDiff addAllDiff = new GraphDiff();
 					foreach	(PositionedNode newNode in newGraph.Nodes)
 						addAllDiff.SetAdded(newNode);
 					return addAllDiff;
 				}
-			}
-			else if (newGraph == null)
-			{
+			} else if (newGraph == null) {
 				GraphDiff removeAllDiff = new GraphDiff();
 				foreach	(PositionedNode oldNode in oldGraph.Nodes)
 					removeAllDiff.SetRemoved(oldNode);
 				return removeAllDiff;
 			}
-			
 			// none of the graphs is null
+			
 			GraphDiff diff = new GraphDiff();
 			
-			Dictionary<int, PositionedNode> newNodeForHashCode = buildHashToNodeMap(newGraph);
+			Dictionary<int, PositionedNode> newNodeForHashCode = BuildHashToNodeMap(newGraph);
 			Dictionary<PositionedNode, bool> newNodeMatched = new Dictionary<PositionedNode, bool>();
 			
-			foreach	(PositionedNode oldNode in oldGraph.Nodes)
-			{
-				PositionedNode matchingNode = matchNode(oldNode, newNodeForHashCode);
-				if (matchingNode != null)
-				{
+			foreach	(PositionedNode oldNode in oldGraph.Nodes) {
+				PositionedNode matchingNode = MatchNode(oldNode, newNodeForHashCode);
+				
+				if (matchingNode != null) {
 					diff.SetMatching(oldNode, matchingNode);
 					newNodeMatched[matchingNode] = true;
-				}
-				else
-				{
+				} else {
 					diff.SetRemoved(oldNode);
 				}
 			}
-			foreach	(PositionedNode newNode in newGraph.Nodes)
-			{
-				if (!newNodeMatched.ContainsKey(newNode))
-				{
+			foreach	(PositionedNode newNode in newGraph.Nodes) {
+				if (!newNodeMatched.ContainsKey(newNode)) {
 					diff.SetAdded(newNode);
 				}
 			}
-			
 			return diff;
 		}
 		
-		private Dictionary<int, PositionedNode> buildHashToNodeMap(PositionedGraph graph)
+		Dictionary<int, PositionedNode> BuildHashToNodeMap(PositionedGraph graph)
 		{
 			var hashToNodeMap = new Dictionary<int, PositionedNode>();
-			foreach (PositionedNode node in graph.Nodes)
-			{
+			foreach (PositionedNode node in graph.Nodes) {
 				hashToNodeMap[node.ObjectNode.HashCode] = node;
 			}
 			return hashToNodeMap;
 		}
 		
-		private PositionedNode matchNode(PositionedNode oldNode, Dictionary<int, PositionedNode> newNodeMap)
+		PositionedNode MatchNode(PositionedNode oldNode, Dictionary<int, PositionedNode> newNodeMap)
 		{
 			PositionedNode newNodeFound = newNodeMap.GetValue(oldNode.ObjectNode.HashCode);
-			if ((newNodeFound != null) && isSameAddress(oldNode, newNodeFound))
-			{
+			if ((newNodeFound != null) && IsSameAddress(oldNode, newNodeFound))	{
 				return newNodeFound;
-			}
-			else
-			{
+			} else {
 				return null;
 			}
 		}
 		
-		private bool isSameAddress(PositionedNode node1, PositionedNode node2)
+		bool IsSameAddress(PositionedNode node1, PositionedNode node2)
 		{
 			return node1.ObjectNode.PermanentReference.GetObjectAddress() == node2.ObjectNode.PermanentReference.GetObjectAddress();
 		}
diff --git a/src/AddIns/Debugger/Debugger.AddIn/Visualizers/PresentationBindings/GridViewColumnHider.cs b/src/AddIns/Debugger/Debugger.AddIn/Visualizers/PresentationBindings/GridViewColumnHider.cs
index 4a715ef318..1ea154e5cb 100644
--- a/src/AddIns/Debugger/Debugger.AddIn/Visualizers/PresentationBindings/GridViewColumnHider.cs
+++ b/src/AddIns/Debugger/Debugger.AddIn/Visualizers/PresentationBindings/GridViewColumnHider.cs
@@ -23,10 +23,8 @@ namespace Debugger.AddIn.Visualizers
 		public bool IsVisible
 		{
 			get { return isVisible; }
-			set
-			{
-				if (isVisible != value)
-				{
+			set {
+				if (isVisible != value)	{
 					isVisible = value;
 					OnPropertyChanged("IsVisible");
 					ExtensionMethods.RaiseEvent(IsVisibleChanged, this, EventArgs.Empty);
@@ -55,7 +53,10 @@ namespace Debugger.AddIn.Visualizers
 		{
 			foreach (var column in gridView.Columns)
 			{
-				var columnWithVisibility = new GridViewColumnWithVisibility { Column = column, IsVisible = true };
+				// show / hide right in the beginning if supported
+				bool isDefaultVisible = (column is GridViewHideableColumn) ? ((GridViewHideableColumn)column).IsVisibleDefault : true;
+				// wrap into our ViewModel
+				var columnWithVisibility = new GridViewColumnWithVisibility { Column = column, IsVisible = isDefaultVisible };
 				allColumns.Add(columnWithVisibility);
 				columnWithVisibility.IsVisibleChanged += columnWithVisibility_IsVisibleChanged;
 			}
@@ -74,8 +75,8 @@ namespace Debugger.AddIn.Visualizers
 		bool canBeHidden(GridViewColumn column)
 		{
 			var columnHideable = column as GridViewHideableColumn;
-			if (columnHideable != null && (!columnHideable.CanBeHidden))
-			{
+			// disable hiding if supported
+			if (columnHideable != null && (!columnHideable.CanBeHidden)) {
 				return false;
 			}
 			return true;
diff --git a/src/AddIns/Debugger/Debugger.AddIn/Visualizers/PresentationBindings/GridViewHideableColumn.cs b/src/AddIns/Debugger/Debugger.AddIn/Visualizers/PresentationBindings/GridViewHideableColumn.cs
index 1e86615558..7be07494f9 100644
--- a/src/AddIns/Debugger/Debugger.AddIn/Visualizers/PresentationBindings/GridViewHideableColumn.cs
+++ b/src/AddIns/Debugger/Debugger.AddIn/Visualizers/PresentationBindings/GridViewHideableColumn.cs
@@ -14,9 +14,11 @@ namespace Debugger.AddIn.Visualizers.PresentationBindings
 	public class GridViewHideableColumn : GridViewColumn
 	{
 		public bool CanBeHidden { get; set; }
+		public bool IsVisibleDefault { get; set; }
 		
 		public GridViewHideableColumn()
 		{
+			this.IsVisibleDefault = true;
 		}
 	}
 }