Hi, I've been following the thread for a while, and am quite impressed with your in-depth analysis of practically everything that goes on in this show... It's like watching the show with some sort of guide... So thank you for all your insights, it has made me much more perceptive as a viewer!
Personally, I think the scar won't appear, because the Hiro who mentioned it was a Future Hiro, in a particular timeline in which Claire had died long before Peter ever knew she existed. So there wasn't really much of a chance for Peter to obtain his healing abilities.
Besides, I think his healing ability is very strong in him because it was the first power he could summon without being close to whoever he got the power from. They could have shown him flying, or shifting his location or whatever it is that Sylar can do when he appears to be flying, or even hearing Claude thinking of pushing him overboard and dodging it.
I think his healing abilities manifested themselves first because he has a strong connection to Claire, stronger than he knows.
I'd be quite disappointed if the scar appeared without a VERY good excuse...
Oh, and this might seem a silly question, but could Mr. Nakamura be Linderman? I mean, Linderman is never shown, and no one has ever seen him (Nathan, Nikki, etc.). Mr. Nakamura somehow knew of Hiro's quest for the sword which belongs to Linderman, and Hiro will somehow get that sword in the future, and, of course, Linderman is connceted to almost every super one way or another, not to mention HRG or Simone.
It could be a different name underwhich Mr. Nakamura operates or something.
As for Simone - Could she be the person Claude was hiding? He would have probably known her as a kid around her Daddy's building. Or is it too much, seeing as almost every person from HRG's job is hiding a gifted child

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I'm sure she has powers, or SOMETHING, not just because she was drawn to both Peter and Isaac, but mostly because of her father and the building. I think she probably knows more than she's letting on.
Or should I say 'knew'?
That's another thing - Peter has met Hiro, and not only that, he met a Future Hiro who can control his powers. How come he didn't stop time or go back in time or do SOMETHING with time the minute Simone was shot?
Okay, these are my thoughts at the moment, I know it's not much but hey, I'm a beginner, please be patient, I'm still learning

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"It is pointless to lie to your God as I am All-Knowing as well as All-Beautiful." - Vala Mal-Doran