How many putts are the Tour Pros' making?
Here's a putting stat from the PGA Tour Shot Tracker that I think puts things into perspective.
It reveals that Tour players on average make:
99% of putts from 3 feet and in
69% of 6-foot putts
54% of 8-foot putts
31% of putts between 10 and 15
I realise comparing Tour Pros to Amateurs' is like apples and oranges, however you can see that anything outside of 6 foot and even their percentages decrease quite rapidly. There for making sure you are making the most probable putts from a percentage point of view makes sense, and will ultimately convert into lower scores much more than holing the odd 15 footer.
