[Mike O]

A lot of times pros don't necessarily aim right at the pin but leave some room for margin - given the hazards on a hole. This assumes two things-

1) that you have some control over your ball flight and
2) that you don't have complete control over your ball flight.

That said- another potential factor besides hazards, green slope, etc. that may determine where you aim might be the balls from your foursome that are already on the green. Assuming you end up inside them on a good line- now you get a "real read" from their putts as opposed to an "imagined read" of your putt. I'm not saying that would 100% control where you aim but it might be one of the factors of many that determine how aggressive or where you aim with your approach shot.

If one found that to be significantly beneficial- then it would not only control your approach shot but also your tee shot. In order for you to be the last one hitting into the green i.e. furthest off the tee - assuming shorter holes where you had an opportunity to let club selection determine how far you hit the ball off the tee.