It appears there is some kind of issue with calling ClearDataSource on a postback and the presence of the "Multiple controls with the same ID error" being thrown when a Template control exists in the WebDataGrid. 

I have a template column with a checkbox and if I use the ClearDataSource call before rebinding the WebDataGrid on a postback I get the "Multiple controls..." error presumably related to the checkbox.  If I comment out the ClearDataSource my postback works just fine and I don't get the fatal error but then, even though I'm rebinding the WebDataGrid (with a refreshed object List<T> collection pulled from the db) on the postback, the OnInitializeRow event handler does not fire again - it will fire on the intiial page load and that's it - which also is a problem as I set some custom cell tooltips when the InitializeRow event is fired - seem's I'm darned if I do, and darned if I don't.  Anyone have any thoughts.