Taker has apparently made it known in the past that he will not put over an "old-timer" at Wrestlemania. He's not a fan of the Streak, but, if they're going to make a big deal out of it, he didn't want it to be ended by a guy near the end of his in-ring career. Rumor has it that he tried to give it to Angle a few years back, then Orton, but Vince said no. Further rumor has it that the plan was to have Punk go over him at Mania 29, but Percy's/Paul's death made them change their mind. They didn't like how far Punk and Undertaker took using the death to build heat (it is worth mentioning that these same rumors say that Undertaker was 100% in support of all of Punk's antics and actually thought that Percy would love the idea that, even in death, he was a big deal in a big-time feud). Had it been anybody but Punk, they would have ended up in the doghouse, but his power backstage is enormous (in a lot of people's eyes, he's actually taken the locker-room leader role that guys like Undertaker and JBL have had in the past).
Either way, the way they "punished" Punk was by not allowing Taker to put him over at Mania. This has led to speculation that there will be a Punk-Undertaker II, in which Punk will go over. Considering his current level of face-hood, though, this is being questioned. Of course, Punk's character, like Austin's before it, is the kind of face that can be heelish and even accomplish the ultimate heel act of beating Undertaker at Wrestlemania, or at least that's what several people are saying (I've even heard the rumor that HHH is one of the folks saying that).
Which is to say that I figure, if they ever do end the streak, it will go to Punk at Wrestlemania XXX. If not, all bets are off as to whether it ever ends.
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