Black Sabbath and Sherwood Schwartz

I've had some odd epiphanies when drinking. Go figure. Ha!
One time when I was at the Empty Bottle in Chicago listening to Rhys Chatham and a bunch of cats on stage doing a multiple guitar riff during his piece GUITAR TRIO, I heard part of a HOUSE OF LARGE SIZES tune. Don't ask me which HOLS piece I thought it was, but it was obvious to me as I stood swaying in the crowd that night.
Last night, while unknowingly celebrating the birthday of Chris Martinez as we drank at the Royale, Marla's iPod played Black Sabbath's "Solitude" from the album MASTER OF REALITY.


I immediately identified its similarity to "The Ballad of Gilligan's Isle" which was, of course, composed by producer Sherwood Schwartz, who did similar work for his other big hit for television
THE BRADY BUNCH. Anyway, I don't read or write or play music, so chime in if you can point out the musical similarities: