Ok, I didn't see the part about deleting using GTC. I avoid that POS. 
Deleting Items
You can delete any folder you have created in History, Workouts, or Courses. You cannot delete the four default folders (Running, Biking, Other, and MultiSport).
You can delete weeks, activities, and individual laps from the History window.
You can delete any workouts from Workout Mode.
To delete an item:
Click the item you want to delete.
Click the Delete icon or press the Delete key on your keyboard. The item is deleted.
NOTE: Items deleted in Garmin Training Center are not deleted from your device. If you do not delete unwanted items from your device, they will be transferred to Garmin Training Center again the next time you transfer your history.
Last edited by SadieKate; 02-21-2009 at 11:25 AM.
Frends know gud humors when dey is hear it. ~ Da Crockydiles of ZZE.