This is something I picked up from TC. If I got it wrong, don't blame him. TC used to say something like to trim your elevator to the bottom of the L on the trim gauge when it looked like you were entering a fight.
TC tends to fly hogs. I tend to fly hogs. In an F4U. trimming elevator to the bottom of the L is just about corner velocity. So, in a fight the nose of my plane wants to go to the speed that gives me the best turn rate. I thought that sounded okay. About that time, I read in Shaw to keep my speed up in a fight so that I could still maneuver in the vertical. Corner velocity allows me to do that, too.
I can still use throttle and flaps to get around in a tighter circle when I get slow. Then I can raise flaps, unload a bit, and when my nose gently pulls up, I'm at corner velocity.
If I'm getting bored to death by a BnZ'er, I'll let trim keep, or get me back, to corner velocity so I can avoid those monotonous passes until one of us does something stupid. I always hope that I can build up some E this way, too, when defending against the BnZ.
At corner velocity, I think I'm at a speed that allows my plane to perform well in a turn and in the vertical. Setting your trim may help your fighting, too.
Of course, Mtnman and snaphook will tell you how predictable I am when fighting, so that may not be a good idea.
HONK!
Gooss