Why did RAF keep using its own Pilot's Notes/manuals when better ones available?

[RCnoob]

I have been researching aircraft manuals and flying methods in WW2. RAF "Pilot's Notes" tended to be short (50 small pages) and especially at first, badly written. I attach a paragraph from my manuscript talking about this, and an excerpt from a 1939 Hurricane manual about how to get out of spins.

What I'm trying to figure out is why the RAF continued to supply its own Pilot's Notes for American aircraft, such as the B-17, B-25, and P-51? The original American manuals were much longer, more thorough, and easier to follow. Why did the RAF go to the trouble of writing new PN's for these aircraft, which as far as I know were not heavily used by the British?

A secondary question, to which I don't expect much answer, is "Why did the RAF choose to write its manuals using its own pedantic style, instead of switching to the American style?" The US Navy, for example, switched to the USAAF style around 1943.

Manuals in both countries evolved throughout the war, so all comparisons have to take the date into account. But that does not change these results.

Thanks for any pointers to discussions of Pilot's Notes, how they were written, and related topics. Other than the symposium I mention below, I don't know of anyone who has looked at this subject.
Roger Bohn

What was in these new RAF (“Pilot’s Notes”) manuals? They mixed descriptions of controls with simple procedures. [Referenced content is missing.] is the pre-taxi procedure from a 1939 Pilot’s Notes for the Hurricane fighter.1 The writing, at least to the modern eye, was formal and pedantic. In 2006 a former pilot described one manual as “[t]he RAF’s Lancaster manual consists of fairly tedious lists and diagrams whereas the equivalent American version for the B-17 contains more ‘cartoony’ graphics which may have helped the reader to get a feel for operating a B-17 more quickly.”2
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1 Hurricane I Aeroplane Merlin II Engine, Air Publication 1564A, volume I, March-1939. Retrieved from scribd.com.
2 Anonymous, “Discussion,” Royal Air Force Historical Society Journal volume 37, 2006, p. 69.

Following is from the 1939 Hurricane manual. Revised March 1940. Surely between 1939 and 1940 someone had developed more details about how to get out of spins.

22. Spinning.- Spinning of Hurricanes is prohibited (A.M.O.A.15/1938). The following extract from an Experimental Establishment report is included in order that a recovery may be made from an inadvertent spin.
“The aeroplane is easy to spin, more noticeably so at the extended aft centre of gravity. [which probably means ‘when the aircraft’s center of gravity is far back’]…
…[several paragraphs of data on height loss in spins, concluding with]
“… The average total height lost from initiation of the spin to attainment of level flight is about 3,800 feet for a three turn spin….
“It appears that the aeroplane emerges from a spin in a stalled state which persists for a considerable portion of the resultant dive if backwards pressure is exerted on the control column. If however the control column is pushed forward in recovery so that no effort is made to flatten out from the dive until a reasonable airspeed is reached, the stalled condition is avoided but the height lost is prohibitive. [In other words, “damned if you do; damned if you don’t.”] It will be seen, therefore, that if recovery is made according to Flying Training Manual Part I., the loss of height during the recovery is normal considering the [Hurricane’s high] wing loading. On the other hand there is fear of flicking into a spin in the other direction because the aeroplane emerges from the spin in a stalled state.
The instructions laid down in the Flying Training Manual Part I., Chapter III, paragraph 134, are applicable to the Hurricane, but should be amplified in light of the foregoing remarks.