Not really. It's all done by computers. This is a weapons platform and the execution of a shot is why it's there.

Remember Luke Skywalker disabling his targeting computer before destroying the Death Star? Yeah, not gonna happen on a military vehicle. Any influence on the vehicle is compensated by computer to get the optimal result.

Besides, slowing down an engine is the worst way to compensate. Angle of the blades is used to get the optimal lift. And it sure needs compensating. Not only the weight, but also the violent way way the mass leaves the vehicle. You could not compensate for that vibration by hand.