I'd say the proper way is whichever way is comfortable and allows you to put your round on target. I wouldn't get too awful caught up in "proper" this that or whatever. That's fine and all for the range, but I would imagine if life would happen to get, uhmmm...intense, proper grips, stances, and tongue positions would find themselves a whole lot lower on the priority list.
Besides, if things hold true to form, a few years from now there will be a whole new catalog of "proper" grips and stances for everyone to learn.