You do realize that RAW is taped on Mondays, and Smackdown is taped on Tuesdays, right? So the champion has less that 24 hours to prepare for 2 main event-ish matches. It is kind of a strain on the wrestler. Includes travel time.
Besides, he has to carry 2 storylines. In the case of HHH, its hard enough for him to carry one.
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Edit: Reread your post. I just realized that you knew all this.
