I think it is an EXCELLENT method for people who have the yips or a "wristy" stroke.
HOWEVER
As i have been helping my friend Andy via the net (who has a real problem with putting), i have told him time and time again these very words when it comes to putting:
"All i care about is if you can trace a perfectly straight plane line while putting. I don't care how you make that happen. But when you find how you allow yourself to do it, KEEP THAT SETUP AND STROKE."
Why you ask? Because once you have a repeatable stroke that traces a PERFECTLY straight plane line the only other thing you have to "worry about" in putting are 2 things:
1) The speed
2) The line
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IMO i don't think there is ANY REASON why anyone cannot find a way to trace a straight plane line with a putter. The stroke is SO SMALL there is NO EXCUSE.
Now this is going to sound arrogant but it's true; I never knew why i was the best putter i ever knew. Nobody who i played golf with (better/worse/club pro/teacher/etc) was better than me. What i found out is that when i bought my Butch Harmon Laser Training aid (bought for the full swing reason) i found out why i putt so well. I trace taht line! Again and again and again and again.
My stroke is so consistent i can literally setup 40* left/right of target, adjust the putterhead open/closed and push/pull putts into the hole because my stroke doesn't change. LOL, come to think of it...ask brian. The first time i went to see him we went to the putting green and setup about 10 balls from about 10-12 feet (left to right putt slightly uphill). I made either 7-8 and i honestly remember missing one because the hole was TOO FULL OF BALLS! Talk about a "lip out"

. All he told me was, "just remember to keep your tempo smooth but i'm not messing with your stroke." Just like brian and the sand, don't mess with me on the green
