Well it's an idea and certainly wouldn't be expected but I think for a truly great heel turn you gotta have an actual 'premise of some sort' going on in the ring.
Like say Michaels wrestling Orton or HHH fighting Edge then Cena runs down with a chair and everyone obviously believes he's coming to the aid of Michaels or the Game, then suddenly he nails them right in the head with the chair...everyone's just in shock, even Orton or Edge. Either one in either circumstance pins one of them then Cena tears into HHH or Michaels with the chair beating him from head to toe, Cena gets on top of either of them and begins punching the hell outta them, either one get's heavily busted open! Then he simply FU's either of them onto the chair...a minor high-end PPV like Survivor Series or SummerSlam goes off the air with Michaels or HHH locked in the STFU all the while JR's screaming "What the hell is John Cena doing?!"..."For God sakes, what the hell's gotten into Cena?!"
Then the next night on RAW he explains everything tearing into the fans...with a great shot in the crowd of a young Cena fan crying (as he no doubt would be or simply a shocked female fan not believing what she was seeing)
^ These are the things that make a heel, sometimes it doesn't work but done properly at the right time with the right guy it would really pay off...in the end it's probley a pipe dream though the WWE would never throw away all that money as Cena is the main attraction for the new generation of wrestling fans right now...but don't be too surprised if we see this in the not-to-distant future
It would have to be the right moment and done prperly to truly work...as evidence here ^
But in my honest opinion I don't think Cena will ever turn heel, it's not like back in the day with Austin where he could afford to see what would happen...Cena's just too important for Vince's young and female fanbase
Is it possible. Yes. Do I think we'll ever see it. No, likely not.
are you sure HHH doesnt wanna have to do with d-x anymore? he still has the comedy left in him
We'll find out when Michaels comes back what WWE does, everything goes through Vince and if he wants it we'll get it...but I've heard Triple H say himself that he doesn't want to revisit the DX thing so I wouldn't count on it