Theoretically, having them behind the baseline could disguise who the in-bound passer will be. I think we've ran a variation of this in the past where the player who starts with the ball passes it to someone else behind the line who then in-bounds it.It does strike me that the proper setup position for the "recievers" might be just in front of the baseline rather than just behind it, for that reason.
I'm of the camp that it's an execution flaw vs a design flaw.