I was in the studio when he was recording one of the songs from Drowning Witch. I don't recall the name of the song, but it has the line "but I like her sister..." with Frank singing. Well, in the studio that night it was Roy Estrada on that part. I had never heard Roy sing live, and I've always loved that Pachuco falsetto. It was so great! But it wasn't going all that well. Frank kept him doing it again and again. Gail came in for a minute and said that Roy really sounded out of tune. Frank had a shit-eatin' grin on his face and said "He always does, but the sound is incredible" or words to that effect. But when the album came out Roy was not to be found. It was Frank doing his low dumb-sounding thing, and it was, to me anyway (who had heard it done differently) a complete disappointment.
There was another time when there was some discussion about just how something ought to go. Frank asked both me and the engineer what we thought. We both agreed on one way. Frank did it the other.