I like using one that we did when I attended a Pelz clinic. I think it was called 'saftey drawback" or something similar. I do this with one ball on a putting green with multiple holes. First you atempt to sink the putt. If you fall short of the hole, then you move the ball back one club length and then putt again. But there is a "safety zone" behind the hole in the form of a semi-circle with a one club length diameter. If the ball stops in that zone then you putt out, otherwise you drawback a club length. This coincides with Pelz's theory that you should strike a putt so that if you miss it will go 17 inches past the hole. There are some who favor just hitting it hard enough to reach the back of the cup--especially for downhill putts.
I have a 50 inch putter so my safety zone is large but my "drawbacks" are penal!
