Funny how our dear Jeff first demands the evidence he has seen a great many times himself (the Spitfire pilot's notes), then when is shown that again he changes the subject and begins to say that the Spitfire's (or any other plane's) operational limitations are not really limitations at all, and they should be adhered only at the pilot's will.
Yeah right, the RAF was busy printing out manuals for aircraft and define their flying limitations simply because they had nothing better to do.