F4U Vs 51D. I have actually experimented with this against some of the best F4U pilots in the game. All fights took place below 5k.
I have fought mtnman where I decided to get on top of his hog, which is the correct move for a 51 to make. (Bait the hog with a bad merge or with a ton of level speed he didn't see you build, and hope he pulls hard into the vert behind you.... then kill him at your leisure).
Although it took me several passes/feigned passes to drive him into the deck, I eventually forced Mtnman onto the deck and he had little to no E to work with. I killed him. Same thing with Saber.
Conversely, I have fought Mtnman where I pressed the dogfight(as opposed to a vertical E fight), disengaging several times to separate a K or so to reverse and re-engage. With my very best efforts, I was unable to kill him. Maybe a better driver could have gotten him but I couldn't. This went on for several minutes, with several merges. I may have pinged him a time or two but I don't remember. This ended , 800 yard (bad)PW for me.. a trip to the tower.
It was clear to me that the Hog/Mtnman combo was the much superior knife fighter to my Steve/51 combo. Again, maybe a better pony driver could have gotten him but I couldn't.
Those were definitely some tough, fun fights Steve! The key is applying the correct amount of pressure to drive me to the deck, 'cause then I'm basically done. If you push too hard, I might land a hit on you as you go past me. Don't push hard enough, and I won't go to the deck.
When I'm being attacked by a faster/higher plane (not that that's how we fought) I actually monitor my speed, and attempt to get higher at every opportunity. I use my speed as a reference. My goal is to get back up to about 275mph after every pass. If I can get to 300+, I use that "excess" speed to climb (at a very shallow angle).
If you push "just right", I'll never be able to build that "excess", and may even have a tough time getting my 275 back. I'll be forced down. Extend too far and take too much time to come in for another pass, and I'll get my speed up and climb a bit. The high guy will be in trouble soon... Push too hard, and you'll be staying too close. I'm going to be looking at shooting at you here and there, and try to pressure you into doing something bad for you/good for me.
I smile when I see the P51 extending less than 2K, or more than 4K. I start to get nervous when he reverses around 2.5-3K and comes back. If he does it a couple times and proves to me it wasn't accidental, I start to sweat.