Michael
Glad to hear about your improvements on the golf course! Although our expertise does not fall in tennis motions, it seems like it would be advantageous to apply this same type pressure to the tennis swing as you would in other athletic motions. If the body loads properly, applying pressure could help the arms, body and racket to move as one through contact. You will notice you most likely already apply pressure when you hit a volley at the net and stabilize the racket for impact.
We would be interested to hear about what you find/experience when applying pressure in your tennis strokes. Thank you, we look forward to any feedback you provide.