I should also point out that the main reason for keeping your hand on the throttle is not so much to make rapid throttle changes during combat, but to prevent it from "creeping back" under all the high G and vibration. In the real world combat flying is mostly done at full power. If you need to slow down it's usually better to pull a bit more G and trade speed for altitude or a tighter turn than to reduce throttle. This is one area wher BoP is less realistic than I would like, but it's still a great game
