SageFIN,
RAE made their measurements using special equipment like free gyro, recorder and electrical timer (NACA did their tests with pretty similar instruments and actually DVL in the Germany used similar procedures too). I don't know if it is possible to measure steady rate of the roll from the AH film, timing should be very accurate and value of the angle should be known exactly.
BTW RAE report contains also following part:
"Some interesting pictures of F.W.190s banking into tight turns have been obtained by R.A.F. pilots during actual combat, and have been communicated to us by the Operational Research Section of Fighter command. Fig.5 shows curves deduced from a typical selection which were taken from the attacking Spitfires with the G.45 camera gun. The films chosen were those in which the backround showed that the Spitfires were not rolling, so that the curves in Fig.5 represent the actual times to bank of enemy aircraft. The speed and height are unfortunately not known, but maximum rate of roll in Fig.4 is about 120 degrees per second."
So the film method was also used by the RAE.
sourkraut,
Basicly heavier ailerons means that more force was required for same deflection iein the chart the difference would have been at high speeds where the stick force was the limiting factor. Anyway, the pilot could feel this heavines throughout the speed range. RAE report says:
"It should be pointed out, however, that where Frise ailerons are used, there is liable to be a variation in the feel of the control from aircraft to aircraft. Our pilots who have now flown three F.W.190s, have, in fact, noticed this variation; they report that the machine on which the measurements were made had rather heavier ailerons than the other two."
gripen