It’s often said that many putting problems exist because the player’s wrist breaks down through the stroke. In some cases, this is true. I’ve noticed, however, that most players who are weak putters tend to allow their trail elbow – not their wrist – to break down through impact, leading to pushing and pulling putts offline.
I see many players extend their trail arm through the stroke rather than maintaining an angle in their elbow. If players learn to maintain the angle in their elbow, it will allow them to putt more with their lat muscles and not their shoulders, which I believe is a key to consistent putting.
You’ll notice a lot of players have transitioned from the conventional grip to the claw grip with success because through impact, the trail elbow does not break down and, as the great Jack Nicklaus described about his putting stroke, the right elbow acts as a piston and pushes the club head through impact.