I'm sure it all varies by degrees, situation by situation, but the idea isn't the point - ideas, as has been repeated ad nauseam, are everywhere. Recognizing opportunities (the factors that make a team predisposed to excel where others with the same idea would not) is much more valuable. A large (possibly larger?) part of the equation should (must?) be team-specific. From everything I've read, the idea will change in the YC process (as it should), the team could drop the original plan entirely and should still be strong enough to do something else better suited to their strengths.

It's hard to read "it's not the idea, it's the team" or "I don't invest in ideas, I invest in teams" and not want to prove someone wrong out of ego or passion/drive. It's difficult to appreciate the truth there without having realized it on your own, no matter how many times you hear that.