For advanced players this drill works great to gain width in your swing and get you to a free release
There are two types of players, those that putt on a path versus those that putt on a line, the path putter work more on feel and seeing a wide path to the hole while line putters are very specific, need a line on their putter head, and see a think line directly from their ball to the hole
Gripping the club too tightly is a fatal flaw in the golf swing, it creates tension in your arms and tightens your muscles and the one thing we know is that tense muscles do not work very fast, causing swing faults and destroying your distance