No dispute that Billups made his bones in the league as a PG. What I was saying was that he was really a SG who made himself into a PG but it took him about 5 years (at least no team of 4 thought he was ready to play that position until Detroit). So there are similarities to Bayless in a way. Like Billups I think Bayless believes that being a PG is his only way to being a starter...he does not have the size to defend other SGs on most nights. And he is right.
Re your last sentence, I dont know that I wrote anything to dispute that. It's definitely an asset to have at any position really and is a must for an elite SG.