When you are running for a backhand ground stroke or volley and you are very late to the ball, most likely having your contact point with the ball behind you, the best grip for the shot is a forehand grip, YES a forehand grip! Your wrist is loose, your racquet face is open and guess what, you can hit quite a shot, whether you chose to be safe or go for it. I guarantee it will work.
When you are volleying a backhand ‘low’ ball off your shoe strings, I find much success with a forehand grip here as well. The idea is similar to a 9 iron in golf, with no effort, your racquet face will be way open and you will have no problem with a backhand slice shot, attaining much lift, all because you used a forehand (eastern, or semi-western)grip instead of a eastern backhand grip or even a continental grip. However, once the bounce is knee or waist high, you must change your grip to continental or eastern.