Post some vids. I would love to see your game, and feel sure that I could learn something.
As for your question, well, check out my sig.
I actually do play 4.0 and above players from time to time. The warmup usually goes quite well. After that it's pretty much downhill for me.
Recently played a solid 4.0 guy. Actually won a couple of games, and I think I made him work a bit in a few other games. How did I win the games I won? Hard first serves went in, was hitting some really hard, slightly undercut driving approach shots that were clearing the net by inches, landing deep and skidding real low, and didn't screw up the volleys.
But of course I can't do that consistently on most points.
Should have made some vids of that match, but didn't anticipate playing as well as I did. As it turned out my level of play was elevated by my opponent's level of play. In the end we were both pleased with the result. Me, because I thought I played pretty well, and him because he won pretty decisively. The old stuff seems to be steadily, but slowly, coming back.