I read somewhere that transfer of movies to DVD causes pitch changes due to a different number of frames per second, or schanning frequency, or something.... Film durations also change as a result. Don't know if it's true.

Is it possible that in the films listed above, if someone had said "Singin' in the Rain, in A" a lot of the non-musicians in the audience would be asking "in a what?" so the film-makers have deliberately chosen key names which would be obvious to everyone.

Although, of course, "in E" would still confuse a Yorkshireman.

Kermit the frog is left handed, which is why a tenor banjo is accessible but a 5 string would be impossible to play. He's still a mean picker, even though they overdubbed him!