Songfacts®:

• Harry Nilsson covered this Beatles song on his 1967 album, Pandemonium Shadow Show. His version is performed at a slower tempo, and throughout lines from other Beatles songs are sung in counterpoint. Nilsson explained (as quoted by Mojo magazine): "One time I was just toying with my guitar. I struck this chord and it seemed to lend itself to a million different songs. I noticed how many Beatles songs could be played on this one chord, so I run down to Wallach's Music City on Sunset, at about midnight, just before it closed, bought the Beatle songbook, and finished the song that night."
• The Beatles spent a fair portion of their listening time in late 1967 listening to Pandemonium Shadow Show. The Fabs were impressed that with this song, Nilsson was taking them on at their own level and not losing out. When a press conference was held in 1968 to announce the formation of Apple Corps and Lennon and McCartney were asked to nominate their favorite American artist, both replied, "Nilsson."
• "You Can't Do That" is widely considered the first mash-up song. By seamlessly blending snippets of about 18 Beatles tracks into a single, melodic consumable whole, Nilsson created a unique and innovative musical piece. While there were instances of combining melodies or lyrics from different songs prior to "You Can't Do That," Nilsson's creation paved the way for the mash-up craze that exploded in the 2000s.