S! bronk.
i think the main difficulty for me when describing flap settings, manifold pressure, etc, etc......etc...is that its happens before ive realised when i'm doing it, i never received any training here about these subjects but after a couple of years it just feels natural. I'm sure you and many others will relate, and its something ive heard many others say.
I guess my golden rules for flaps are:
1: If i want to burn energy off, hit flap down button too many times very quickly.
2: If my aircraft feels unstable due to lack of lift(climbing a rope, looping, etc), drop another notch.
3: If my aircraft feels unstable due to air flow over the wing(snap stalls, nose bounce, spiral death dives and flat spins), lift a notch or two.
4: If my aircraft has finished 60% of a turn/loop and my enemy seems to be extending, lift them all real quick and chase the bugger.