Okay, here goes Eric...
Hiro from the future, or present (not sure on this point), stabbed Sylar, but he regenerated and still destroyed the city. Future Hiro figured that if he saved the cheerleader, he would have been able to kill Sylar, so the "save the cheerleader" plot started. Unfortunately for him, saving the cheerleader was not enough because through that Peter was set into a course of action where he became the bomb.
When he said he stabbed Sylar and he regenerated he was talking about before the Cheerleader was saved. But he was wondering what happened that the city was not saved.
Whew.
No, you made my point.
There should have been no "Future Claire" for him to kill and eat if he had already survived.
See my only question is whether or not the Future that Hiro and Ando went to reflected the present actions after they had already Saved The Cheerleader etc.