would you please provide some additional details on your automation challenge.
You can easily keep re-getting the value from a single textblock. For instance:
SilverlightApp sl = ActiveBrowser.SilverlightApps();
TextBlock b = sl.Find.ByAutomationId<TextBlock>(
String temporaryValue =
temporaryValue = b.Text;
Unfortunately, I cannot offer further assistance without additional information on your usecase. I hope you find this sample useful.
the Telerik team