ECW allowed Punk to be introduced to the WWE "Universe" (although him winning the ECW Title from Big Show in the Elimination Chamber would have sped up his career).
Winning MITB got Punk noticed. Winning the WHC right afterwards showed Punk had some respect in the back and was his first shot at the big time. He failed to really get over.
The Hardy feud showed how good he could be as a heel (although you'd think the anti-drug character would be the face in the feud, but.....#wwelogic).
The SES showed that Punk could be the top heel in the company (there just wasn't an opening for the spot at the time, then Creative took over and f**ked the angle up).
The "shoot" and the ensuing feud with Cena/McMahon/etc. are what has made him the #2 guy and top heel in the company.
End result: Hardy played an important part in his development as a WWE performer, but the talent has always been there. Just watch the "Summer of Punk" DVD that ROH put out. I do agree with something that Heyman says on the BITW DVD: WWE initially didn't have a clue what to do with Punk, which probably cost him two years or so of his career.
Oh, and TNA fan that I am, Punk > Hardy.
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