Lyric discussion by Dia270 

Cover art for Grown So Ugly lyrics by Captain Beefheart and the Magic Band

According to John French's book, Ry Cooder wrote the "knock upon my baby's door" verse (the important part of the song!) Cooder found the song and drove everyone mad rehearsing it. (Especially Don - his own "blues" songs were full of irregular phrasing and rhythms but he didn't like to memorise anyone else's irregularities. No wonder Zappa had so much trouble with him)