It's a team sport, Guy. One guy alone means nothing. That's what makes the Pistons so tough.
The Pistons are unusual in that they have a collectively strong starting 5, none of which are superstars or (with the possible exception of Big Ben) irreplaceable. On the other hand, without Wade the Heat offense completely breaks down since he's the only guy on the team who can routinely drive to the basket. I think the "no Wade in game 7, no Heat victory" is a safe, rational assessment.
(I agree with you that those are the breaks, though.)
When healthy and putting up his regular season numbers, you might be right. But I think at this juncture Wade is more important to the team than Shaq is.
Guy