RE: Can you answer this?
OK I thought we were talking theory here I guess not. You could line up a hundred planes that do not need rudder linkages to fly at 70 mph with no flutter, does not address the underlying theories.
You have never heard of balanced surfaces to prevent flutter? If the surfaces are not balanced, and 'unbinded" rudder and fin can transfer energy back and forth,. That is what causes fludder in the first place.
My last fast jet did about 282 mph, so I have heard of it.