By his own admission (Wings of the Navy) Eric Brown didn't fly the Corsair for the first time until Feb 1944, by which time regular FAA squadron pilots had been flying it for nearly 9 months. He himself adds to, or restates, the "myth" by noting:-
".....the only problem was that a further two-and-a-half years [from the first flight of a production F4U-1] were to elapse before the US Navy was to consider it suitable for shipboard operations!"
And
"Oddly enough, the Royal Navy was not quite so fastidious as the US Navy regarding deck landing characteristics and cleared the Corsair for shipboard operation some nine months before its American counterpart."
He seems unaware of what went on in the USN in 1943, and seems to be referring to the F4U going aboard the US fleet carriers at the end of 1944 (see below). By Feb 1944, Illustrious had 2 squadrons aboard in the IO.
The F4U Corsair was an aircraft he had, in his own words, an "unenthusiastic regard" for! Plenty of criticism about the way it handled.
The USN, having sidelined the Corsair, in late 1943 for logistical reasons (except for some F4U-2 nightfighters in 1944) brought it back in Dec 1944 because of the immediate need for more fighters to deal with the kamikaze menace. What was immediately available in Hawaii were two USMC F4U-1 equipped squadrons which went aboard the Essex at the end of Dec 1944. Another 2 squadrons were allocated to each of Bennington, Wasp & Bunker Hill and Franklin between Dec 1944-Mar 1945 in time for Iwo Jima. This was only intended as a temporary measure pending arrival of new USN CAGs with enlarged fighter complements. They stayed on Essex, Wasp and Franklin until March (when the last named was kamikazied & put out of the war), Bunker Hill until May (when she was kamikazied) and Bennington until June.
USN F4U-1 equipped squadrons began turning up in TF58 from March 1945 as part of the replacement CAGs for Essex, Wasp, Franklin, Intrepid and Hancock.