Sure!
The grip's form should be drived from its function, so that the form optimally performs the function.
So, what is (or are) the function(s) of the grip?
First, to hold the putter and connect the putter to the body. Second, to help move the putter in the stroke. Third, not to mess up the putt.
Holding the putter is simple enough. You can do so with two fingers or just one hand. Holding also implies sufficient grasp of the handle so that the putter doesn't slip lower from gravity or the inertial forces in the stroke. So, the first function doesn't really tell us much about form, and tells us a little about pressure.
Second, helping to move the putter can mean a wide variety of things. I do NOT mean that the hands and wrists are involved in guiding the putterhead or in powering the stroke or in any other manipulation of the putterhead or face. What I teach is that the grip must "monitor" the stroke to make sure the movement of the putter is not too fast or out of track for the stroke plane. What's to monitor and how?
If you start the putter back from address too sharply, the handle will waggle inside your grip butt-end targetward.
If you stop the putter too abruptly at the top of the backstroke, the handle will again waggle inside the grip the same direction.
If you start the putter down in the downstroke too quickly, the handle will waggle inside the grip butt-end backwards.
If the grip is too light at impact, the handle will waggle inside the hands butt-end targetward.
If you power the putter down into impact with the hands and wrists and forearms, the putterhead will lag and the handle will waggle butt-end targetward.
At the very least, powering the putter with the hand will result in increasing pressure in the grip and you will feel the tightening if you pay close enough attention.
Similarly, grabbing at the putter in anticipation of impact communicates a grip pressure change.
If you have a left-wrist breakdown through impact, the putterhead will pass the hands and the handle will waggle inside the hands butt-end rearward.
If the face twists open in the backstroke, you will feel it inside the grip and probably also in your thumbs.
What all these have in common is that the grip HOPES to feel NOTHING AT ALL during the stroke except exactly the same contact the hands and fingers have with the handle as when the hands are still at address. Any feeling of pressure change inside the hands during the stroke is a sure sign of trouble, mostly from poor tempo control, but also from hands getting into the act when they should be dead. This criterion tells us quite a lot about grip form and grip pressure.
The third fucntion is a negative. Some grips hurt the stroke pattern because of their relation to the rest of the body. The biomechaical relations of torso, shoulders, arms, wrists, and hands teaches that a "palms opposed" grip would tend to preserve the face angle at address for impact. Excessive grip pressure robs you of touch and overly involves muscle groups that have little or nothing to do with a smooth, straight stroke with good touch. Grips that cause the shoulders to get unlevel also deloft the putterface, alter the relationship of the putter sole to the surface, and alter the position of the hands with respect to the bottom of the stroke arc, all of which affects accuracy and the quality and consistency of the roll.
So, I recommend a palms-opposed grip that does not make the shoulders unlevel, that has a constant relatively light grip pressure, that has good handle contact inside the grip, that allows the forces of waggling or twisting in the handle to register in the skin of the palms and fingers, and that does not encourage the hands to get involved in guiding or powering the stroke. You also don't want the grip involved in starting the stroke back, either, as this usually sends the putter outside the line and/or twists the face.
In a true dead-hands shoulder pendulum-like stroke, the buggaboo of left-wrist breakdown is a false issue, since only hand powering in the stroke or premature deceleration in the arms results in left-wrist breakdown. In the shoulder stroke, keeping a basic minimal muscle tone to keep the triangle intact, plus not stooping the stroke prematurely in the follow-through, is all that is needed to avoid left-wrist breakdown. So I don't really understand the reverse overlap grip as anything other than a band-aids that perpetuates handsiness or poor stroke control.
Similarly, since in a true pendulum stroke, you need to respect the bottom of the stroke, and reach it squarely just before impact, so that the bottom half of the rising putterface impacts the ball on a slight upswing for a straight, good-quality roll with consistent energy transfer, grips that cause unlevel shoulders should be avoided. For this reason, the "left-hand low" grip is not optimal, even if many find it beneficial for overcoming their flaws. It delofts the putter and encourages a downward blow to the top-quadrant of the back of the ball that pinches the ball into the spongy turf momentarily, causing ther ball to rebound up and waste some energy. This posture can also cause head and eye positioning that is not great.
The grip I devised is basically a left-hand low grip without the unlevel shoulders. With left-hand low, the right hand covers the little finger of the left hand. I just move the right hand down, with both index fingers extended straight, so that the last three fingers of the right hand cover the last three fingers of the left hand. This makes the right hand lower than the left by only one thumb nail, or half a finger width. The index fingers are not rigidly extended and in fact "rest" against the shaft so as not to encourage the powerful index fingers to try to guide or manage the stroke. The left hand has the handle laying down along the life line of the palm, so that when I angle the wrist down like a fisherman making a cast, the shaft of the putter matches the line of the forearm. The meat of the thumb pad secures the handle into the knuckles of the three fingers (not onto the pads of the undersides of these fingers. The left thumb is straight down the top of the handle so that the top half of the fingerprint is securely in contact with the handle (not smushed tight or flat). The right hand is pretty relaxed and just rides along to help keep the triangle intact. On a scale of 1 to 10, with 10 being the tighest I can squeeze my left hand, my left hand grip pressure is between 2 and 3, definitely light but not goofily so. I call this the "Pistoleros" grip, since it looks like two pistols.
The way the grip actually fucntions is that if I start with a grip pressue that does not kill out subtle waggling or twisting of the handle, I simply turn the shoulders in a rocking back with the triangle muscle "tone" about the same as the grip pressure and monitor the stroke with my palms and fingers. Sometimes I will actually point the left thumb at the putt line as I go back and through, both to help keep the stroke on plane and to keep the face square. The thumbs tells me more about the face than the palms or fingers.
With this grip, it is really a left-hand-only stroke, with the right hand playing a "supporting actor" role. In fact, if you take up the grip with the left hand only and then use the right fingers to lift the shaft back to the top of a backstroke, and then release the putter, you will get a very satisfying stroke, with nothing happening in your left hand other than staying at the same tonic pressure.
This grip works fine for me. It really promotes care in how the left hand and arm get moved by the shoulders, so the stroke stays in plane, the face stays square to the plane, and the tempo is nice and smooth.
Cheers!
Geoff Mangum
PuttingZone
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