"Tightness of their songwriting" is certainly one of of saying "like it was written by a seven-year-old." Unless it's something like Lucy in the Sky With Diamonds, at which point you don't get credit for just writing random shit like a 00's kid trying to be funny because you're high as fuck. All sang in a four eunuch harmony with basic bitch composition because it was the 60's and standards were non-existent at the time.
But occasionally they'd bust out some drug-fueled jam session so actually they were geeeeeenyussis. Not counting when Lennon stole a track from Zappa, of course.