I'd have to know just how close the race to the stall was in order to judge the Mayor's admittedly bold action of rapping on the door and trying to assert his "key to the city" privilege.  If it was obvious to both of you that there was a common objective, and you came from behind and just barely overtook him at the bathroom door while at full trot, I think that puts a different spin on the story ;-)  Let me put it this way-- if someone cut me off like that, I'd better not hear a newspaper rattling in the stall, or I might be knocking, too ;-)