When I first joined the Tour in 1969, it was littered with weak grips. I'm not talking about grip pressure (some of the guys could squeeze bricks into dust, or so it seemed), but rather the position of the hands on the handle. Almost everyone turned their hands more to the left, so that the Vs formed by the thumbs and forefingers pointed to the right side of their chest, and sometimes straight up at their chin. If your grip was any stronger, the old guard (say, a guy like Gardner Dickinson) would smile, pat you on the back and mutter, "You got no chance with a grip like that, son."
My grip was neutral by pro standards -- I basically clapped my hands together and took my hold from there, with the Vs pointing toward my right ear. The key was to point the base of the Vs at the ball at impact. That gave you a straight shot with a less-than-strong grip, and this technique was popular well into the 1980s. But ever since, grips on Tour have become stronger and stronger.
I think I know the reason. Today's game is more about hitting it long than straight, especially off the tee. If you can’t drive the ball 290 yards, you'll have a hard time keeping your Tour card. (I'm starting to sound like Gardner Dickinson -- yikes!) And when your goal is to get that clubhead moving as fast as you can, your grip has to be strong enough to handle the extra speed, to keep the clubhead from releasing too early through impact.
Big hitters like Dustin Johnson use a strong grip, and if you went to a Tour practice range, eight out of 10 holds would be strong ones. It's a sea change. Those Vs that used to point at the right side of the chest? Some now point outside of the right shoulder!
Everyone wants to hit it farther, so if your weak grip is causing weak contact, rotate both hands to the right on the handle. Point the Vs at your right shoulder. It may feel weird at first, but trust me, it pays off. A stronger grip lets you pull harder with your left triceps on your downswing (hello, speed) without worrying about the face flipping open, a problem in the weak-grip era.
A strong grip is one reason today's Tour pros hit wedges as far as I used to hit my 8-iron. As long as you turn your body all the way through in the downswing, you'll square the face in time for impact and not only hit it farther but straighter, too. And if you slice, the new Tour grip is just what the (swing) doctor ordered.