REVERSE TAPER BREAKTHROUGH.
The top hand controls how square your club face is to the ball. Unwanted rotation from the top hand translates to a club face that is not square at impact. The amount of rotation transferred is directly related to the thickness of the grip in the top hand. By using a reverse taper RD grip, you get more thickness at the lower hand to stabilize your stroke, and less thickness in the top hand to quiet any twisting movements through the stroke. This increases your putting accuracy by keeping your putter face square to the ball.