At the end of the day, the debates don't affect the election. Even if 99% of the public thought Obama had won, the race would be unaffected.

They're not determinative by themselves, but they most certainly can have some effect.

Nate Silver is saying Romney may go up 3%.

So none of us knows.

We may be worrying too much, or we may not.

Time will tell.

Casual viewers have to believe rmoney is capable.
and the press will get behind that notion.

A debate is probably only going to sway an undecided voter who is looking for one of the candidates to say something about a particular issue the voter thinks is most important to him/her. Whether either of them touched that base is a matter of conjecture.

I think just about every voter considers that someone who wins a major party nomination is "capable".