I am not sure why you want to start on semantics. I can say a person is too tall if he is 40 cm taller than the average without knowing what the high of the tallest person that existed.
Again try to keep it on subject and simply compare the acceleration and rotation of other vehicles with that of the Churchill.
I'm not sure you understand what 'too' means in this context.
It's comparative. It can't exist in isolation. You have to be too something to something.
If a theme park ride only allows people under 180 cm tall to ride it, and a man is 185 cm, then he is too tall to ride it.
You're saying the rear armour (or rotation speed or acceleration) is too high to be balanced, yes?
If that is true, then there is a maximum rear armour value for the Churchill that is not too high to be balanced.
For that to be objectively true, that value has to be defined objectively.