Index: /trunk/autoquest-core-tasktrees/src/main/java/de/ugoe/cs/autoquest/tasktrees/temporalrelation/utils/TaskTraversalMyersDiff.java
===================================================================
--- /trunk/autoquest-core-tasktrees/src/main/java/de/ugoe/cs/autoquest/tasktrees/temporalrelation/utils/TaskTraversalMyersDiff.java	(revision 1847)
+++ /trunk/autoquest-core-tasktrees/src/main/java/de/ugoe/cs/autoquest/tasktrees/temporalrelation/utils/TaskTraversalMyersDiff.java	(revision 1848)
@@ -15,5 +15,5 @@
 package de.ugoe.cs.autoquest.tasktrees.temporalrelation.utils;
 
-import de.ugoe.cs.autoquest.tasktrees.temporalrelation.TaskInstanceComparator;
+import de.ugoe.cs.autoquest.tasktrees.temporalrelation.TaskComparator;
 import difflib.ChangeDelta;
 import difflib.Chunk;
@@ -33,10 +33,10 @@
     
     /**  */
-    private final TaskInstanceComparator comparator;
+    private final TaskComparator comparator;
 
     /**
      *
      */
-    public TaskTraversalMyersDiff(TaskInstanceComparator comparator) {
+    public TaskTraversalMyersDiff(TaskComparator comparator) {
         this.comparator = comparator;
     }
@@ -102,10 +102,7 @@
                 // but the algorithm is one-based
                 // that's why there's no +1 when indexing the sequences
-                synchronized (comparator) {
-                    while ((i < N) && (j < M) && comparator.equals(variant1.get(i), variant2.get(j)))
-                    {
-                        i++;
-                        j++;
-                    }
+                while ((i < N) && (j < M) && comparator.equals(variant1.get(i), variant2.get(j))) {
+                    i++;
+                    j++;
                 }
                 
@@ -169,11 +166,13 @@
             
             Chunk original = new Chunk(ianchor, variant1.subList(ianchor, i));
+            int originalSize = original.size();
             Chunk revised = new Chunk(janchor, variant2.subList(janchor, j));
+            int revisedSize = revised.size();
             Delta delta = null;
             
-            if ((original.size() == 0) && (revised.size() != 0)) {
+            if ((originalSize == 0) && (revisedSize != 0)) {
                 delta = new InsertDelta(original, revised);
             }
-            else if ((original.size() > 0) && (revised.size() == 0)) {
+            else if ((originalSize > 0) && (revisedSize == 0)) {
                 delta = new DeleteDelta(original, revised);
             }