Dear James,
Breaking putts present three separate challenges: 1) aiming high enough, 2) setting up on slope to avoid losing the putt downhill / low side, and 3) avoiding pulls (mostly) or sometimes a push. If you handle each of these well, there is no reason for stroke gimmicks.
On the other hand, the Seve technique of putting "right to left" putts (for a right-hander) off the toe tends to solve these three challenges in an artificial way. Hitting the ball off the toe tends to open the face of the putter and direct the ball higher than the stroke otherwise would send it, thus addressing in a fashion poor aim (not aiming high enough to start with). By the same token, off-the-toe impacts similarly avoid pulls and losing the putt downhill.
The problem is that this approach is a sort-of approach. There is no way to anticipate exactly how to stroke the ball off the toe -- a little slower, a little farther out towards the toe, a little faster but far out on the toe, with a loose grip that allows the putter face to open ... etc. So this method is very "touchy-feely." If you are good at "touchy-feely" putting, and consistently so, and not streaky (as almost everyone on earth EXCEPT Seve Balletseros probably is), then this gimmick is a pretty good way to putt while avoiding dealing directly with the underlying challenges of aim, setup, and stroke.
Different putters, gripped in different manners, and used with different setups and strokes, result in different effects when used with this off-the-toe approach to breaking putts -- to say nothing of the variations in the green slope and contour or the distances and break involved.
So, you are correct to suspect that this approach to breaking putts is not my standard recommendation. I'd rather see the golfer face the real challenges straight up. If not, I'd have to see whether the golfer was very good at "touchy-feely" putting. If not, I'd be rather insistent that this off-the-toe approach is not that good.
I'm not aware of any studies performed about the effectiveness of this approach to putting breaking putts. The problem would be in figuring out just how good or bad some of the test subjects are to begin with in handling the basic underlying challenges of aim, setup, and stroke. If this is not separated out of the testing, all you get is a general sense of whether this approach helps indifferent players do a little better on breaking putts than indifferent players do when trying to use better technique (that they may not be too good at performing). This still leaves unexamined whether a good player using good technique well putts better by handling the aim, setup and stroke directly or whether the same good player gets better results using the "touchy-feely" off-the-toe technique.
Cheers!
Geoff Mangum
Putting Theorist and Instructor
Geoff Mangum's PuttingZone
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