First, we need to find out whether BB was honest, partly full of ****, or completely full of ****. Any other coaching blame has to take a back seat to the QB play/not play situation.
Him telling Aikman that he planned to use both QBs (during the announcer game prep interview), and his comments at the half, would seem to indicate that BB is not being completely full of ****, and maybe only partly full of **** in the sense of the timing of the change, if at all, but some here seem to want to believe otherwise.