The Beatles - The Greatest Progressive Rock Band Of All Time?

Lets not forget The Beatles "Magical Mystery Tour" also very progressive leaning. The Beatles definitely were drivers during the Protoprogressive era! (yes I said it) They laid the ground work. They changed music forever and sent rock music into a more progressive era. Love was also a band that pushed it in the sixties. But I have to say I think that Yes and Pink Floyd are the "Progressive" bands that created what we now know as progressive music.
Zappa too but his style was more free-form which puts him into some weird Jazz thing for me...