Anybody else have a problem with Jack's plan at the end? (SPOILER)

Twords the end of the film Jack calls Whistler and tells him he's decided to give up Hap. This is a ruse to draw Whistler out. However, Jack's plan is to dress Hap up in his trench coat so Whistler will think it's Jack. Whistler then sees Hap dressed as Jack standing on a street corner from the top of a building, and opens fire on Hap.

First of all, Jack is supposed to be protecting Hap. So he puts him right in harm's way? Even if Jack knew Whistler to be a lousy shot, what if Whistler got lucky? Also, can you try to imagine Jack trying to get Hap to go along with it? ("I'm going to dress you up in my clothes and this guy who's trying to kill me will shoot at you. Be ready to dive for cover.")