I’d be willing to bet your grip pressure is way too strong. Not strong like you’re going to hook the ball every swing, but strong like Sylvester Stallone’s grip probably is. The vast majority of golfers I meet strangle the club. Extra firm grip pressure is very damaging to the golf swing; it creates muscle tension along the forearms, up through the biceps, into the shoulders, and through the rest of the body. A great golf swing is fluid and smooth and when the muscles are tense that is difficult to achieve. If you’ve got blisters after a round, or big calluses, you’re gripping TOO HARD! Sam Snead compared the golf grip – which is the foundation for all swing mechanics – to holding a small bird in your hands; don’t crush and kill it, but don’t let it fly away either.