People who say things like "OMG The Beatles smoked pot and look at what they accomplished!" are deluding themselves. The Beatles would have gone down in history with or without drugs. The drugs just happened to be "the thing" at the time, and it took them down certain musical paths.
And they never actually recorded music while high. The only ones who did that were the Grateful Dead, and they sucked.
it probably did help them. it's an artsy type of drug. music is art. when you're high all these melodies and lyrics pop up in your head that u probably wouldn't think of otherwise. if they didn't start getting high they might've been making songs like do u want to know a secret for a couple more years, still the best boy band style music ever made(only good boy band music), but weed helped them evolve as a band faster i think.