A general question about maneuverability

[klemchen]

Hello everyone,

in aviation literature maneuverability is often treated as something unambiguous. However, there are different ways of determining this quality: For instance, one could ask for the smallest possible circle an aircraft can fly, with or without loss of altitude permitted at any or at some specified altitude, or one could consider the shortest time which an aircraft needs to fly a full circle, with corresponding variations.
By logic, these concepts are clearly not the same, but they still could be factually equivalent. This would mean that, by laws of physics, if of any two aircrafttypes 1 and 2 one turns out to be better according to mode A it also does according to mode B. In other words, modes A and B would not be (factually) equivalent, if there are instances of two aircraft types 1 and 2 where type 1 is better according to mode A but type 2 is better according to mode B.
I would expect that not all reasonable concepts of maneuverability are factually equivalent, but I do not know this for sure. If this asumption is correct, then what kind of maneuverability is most important concerning air combat? -
It is generally agreed that the Spitfire and the Hurricane were distinctly more maneuverable than the Me 109. In spite of this, Len Deighton in his book "Fighters" stated just the opposite. I do not have the book but some time ago I read the passages on the maneuverability of those fighters. If I remember it correctly, Deighton took as criterion the smallest possible circle that could be flown at a certain rather high speed. I have read statements that Deighton is downright wrong, but could it be that instead he was also right, except that his claims are based on a rather unusual criterion?
Any answer will be greatly appreciated.

Best regards,
klemchen