Sounds like that nails it. So the instruction I got went like this....
Take your hand and make a 90 degree L with your thumb and forefinger. Take the handgun, unloaded and all that, and mate the top of the grip with the web of your hand, high up and tight in the dovetail area where it is suppose to be. DONT close your hand yet! Line the gun to be making 45 degree angle, bisecting the angle of your thumb and forefinger. Now, moving ONLY your trigger finger, wrap it around and place it on the trigger in proper ‘pulling the trigger position’ (usually the meaty part of the tip but that can vary). Now wrap the rest of your hand around the gun putting pressure from the front to the back of the grip and not squeezing the sides at all. Now your take your other hand and lay the big fatty base of your thumb in the open space on the grip between your fingers and thumb.
When I did it the way he described it felt weird. My hand was shifted farther around to the back than I was use to. Even now it feel odd. But dang if it does not make for the straightest shooting grip I have ever tried. It controls recoil very well too. With or without the second hand it is very secure. Strangely, with the hand shifted that far around, your thumb does very little. It can almost be flapping around lose, a condition I had always cautioned people against when I was instructing, with no lose of grip strength.
Sounds like that nails it. So the instruction I got went like this....That seems to work for me, too. It seems the design of the P7 forces your hand into that configuration. But I tried grasping another gun as if it were a squeeze-cocker, too, and got the same results. Now to try it on the range with another handgun, too.