So what you’re really saying is due to boundary layer dynamics a flapping jacket that flaps just enough to delay flow separation is in fact faster than no flapping jacket. Proving that more noise to a point is faster than no noise. 
So what you’re really saying is due to boundary layer dynamics a flapping jacket that flaps just enough to delay flow separation is in fact faster than no flapping jacket. Proving that more noise to a point is faster than no noise.