[daodedickinson]

Brood War hasn't had to ban a whole unit or building, though.

EDIT: Now that I think about it, the narrow ramps that you see in the campaign are banned for competitive maps because units like Dragoon will simply never go up or down one unless babysat the whole way, one by one, clicking a few pixels further with each move command so that the Dragoon doesn't go backward. Brood War is full of unbalanced and unworkable mechanics and was fixed not by Blizzard patches, but by literally professional pro map makers.