You are all wrong.
You overlook the obvious.
You speak of short game and confidence and some double-secret level of game mangement, and it's all true. The pros are better at that than the average guy.
But the NUMBER ONE reason they're better than us is the old Chicago Golf slogan: Far & Sure.
They simply hit the ball better than us. They hit it waaaaay farther than the average decent handicap player and they hit it waaaaaay straighter waaaaay more consistently.
THAT is the #1 difference. Everything else is vying for #2. Dems' da facts.
Shiv-
This used to be the case...but I'm not so sure anymore - at least not the farther and straighter bit. Sure, they hit the ball more consistently solid than any of us do...but that is true of the gap between any level of players, not just us and pros...
But with the advent of "Bomb and Gouge" I really don't think it has much to do with hitting the ball straighter. Off the tee, they're hitting it more crooked than ever, and I think many of us would agree that a guy hitting the ball 330 in the rough will probably not score as well as the guy hitting it 280 in the fairway (a human distance)...citation: Tiger at Hoylake.
Short game is certainly what separates the top flight pros from the journeymen, but it's also what separates them from us. I was being a bit overdramatic by saying its wedge trajectory only, but that's the one thing I was most struck by when watching them live.
A great many things I can do with my game can be more/less pro level - I can hit the high booming 300 yard draw on occasion with my driver...I can fade a low 5 iron around a tree...I can work high and low iron shots both ways...but I cannot for the life of me hit a 95 yard sand wedge at the trajectory they do and with the varying levels of control they do. I can't hit a 60 yard sand wedge that flies in low and goes bounce bounce stick.
Oh and the above mentioned things about my game? Well, those don't exactly happen regularly - the rule is the mishit and the poorly executed golf shot - but I'm just saying that it's not farther and straighter...but certainly more consistently excellent. I just think there are enough guys in the world that can hit the ball long and straight (hell, you're one of em) and yes, theres a gap between you and I and even a guy like Mike Weir in that department, but the gap is nowhere near as pronunced as the gap between us and them from 100 yards and in.
Give me 10 balls and the following choices in a beat the pro competition:
1) Driver - ball must end up 290 yards or farther from the tee and in the fairway
2) PW 125 yards - ball must end up inside of 10 feet to a front right pin
3) SW 85 yards - ball must end up inside 5 feet
4) SW 30 yards - ball must end up inside 3 feet
Distance is the obvious thing to point to, but I think that overlooks the fact that a great many of people have the length to compete with the bottom 20 percent of players on the tour by distance, but the bottom 20 percent of players on tour's short game from 100-125 yards in will dance circles around EVERYONE'S short game, bar none, until you get into scratch or better territory.