i'm assuming from your description that you haven't created the Call Graph that Chris was referring to.
If you select the OnPropertyChanged method from the TreeView you will notice an icon appears in the selected row. If you create a call graph by clicking on that graph the view may reveal something a little more informative about the issue.
The other point you raised about the simplified stack trace in the TreeView is a measure that we implemented to help reduce the impact of profiling on the performance of the application. This option can be turned off so that you see more methods (although the stack trace could be huge as a result) by going to Tools > Options prior to starting profiling and unchecking the "Simplify very complex stack traces to save memory" option. This may have a negative impact on profiling performance.