Was just listening to some great interviews on YouTube with Bill Bruford, and although he respects the fact that there is good pop music that has caught on with the masses over the last 50-60 years, it is clear that The Beatles et al. , musically, is really the very simplest arrangements of music available. For real music, Mr. Bruford keeps going back to Jazz and such as the "musician's music"..... if one is concerned with pushing the boundaries of what music is and can be. Some good pop music pushed things a bit, such as his bands Yes, King Crimson and others like old Genesis, Gong, etc. etc. etc., but even he admits they were still on the "primitive side" ...... like the Beatles is kindergarten, King Crimson is grade 4, but great jazz is like high school .....