I can respect that decision, since it doesn't change the premise of the game. (I should note it didn't detract from the game at all)
Another idea you could do, or at least could improve it until the hammer swing impacts are figured out: Have the collision box reach before the first hammer swing so the players can't walk passed the hammers, and then have an overlap trigger *slightly* before the collision box that gives the caption "Those are going far too fast to attempt to walk through!". :)