Many golfers putt with their forefinger extended down the shaft of the putter. They do this in trying to control the face angle and the path of the putter head.
However, the downside to this is that it adds lots of tension in the wrists and forearms, allowing the golfer to manipulate the stroke, instead of allowing the stroke to happen naturally.
We suggest that golfers avoid putting with their finger down the shaft and instead have a light grip, with relaxed, straight arms and rocking the shoulders to initiate the putting stroke. This will enhance rhythm and the swing path, improving distance control and accuracy.