Spit IIa

[Crumpp]

Isn't a little bit of unstability good for maneuverability?

Not at all. In fact that is big myth.

Remember, a stable airplane can do any maneuver an unstable aircraft can. The stable airplane can do it just as fast and more precisely requiring a less skilled pilot to do the same thing. It can also do things the unstable one cannot. Such as not destroy itself by overloading the airframe, shoot down other airplanes much faster, land with more control and precision, maneuver better in rough air, and hold a precise altitude/heading in instrument conditions.

Unstable just means the airplane is skittish and hard to control.

I'm not convinced that it was a problem though

Sure it was....

The RAE even recognized it attempted to fix it. Eventually it was eliminated in the very late marques with an empennage redesign.