Okay, here's the deal. Consider it a hypothetical situation, since it may be one huge longshot.
It seems like a lot of people are overlooking the fact that if Shawn Michaels and Undertaker wrestle at Wrestlemania, it doesn't need to be for the World Championship. From what I can tell, Michaels isn't as concerned about the championship as he is about making up for last year and ending 'Taker's streak.
Thus, how feasible would it be for Michaels to win the rumble, whereas 'Taker loses his title to Mysterio? Would it be possible for Michaels to win the Rumble and forego his title shot in order to wrestle 'Taker at Wrestlemania?
And in turn, could that then lead to Mysterio wrestling CM Punk as many have speculated, only now it would be a hair/championship match instead?