Quote Originally Posted by Raum View Post
Some amount of grappling can be done with little or no grip - several Judo and Aikido throws come to mind.
Going more basic - fundamental wrestling underhooks can be done without that much grip.

If the other hand is free, possibilities remain even higher - all in all there's whole lot of locks and stuff performed with sword/weapon in the other hand in Talhoffer and other guys works.

Still, options are limited, even if you can work around it well.