Back atcha, brother. I saw The Dead in ’67 (in the Panhandle at Golden Gate Park), with Ron (Pigpen) singing. I liked that first album a lot, and the next few that followed. But when they started trying to sing harmonies (that had became all the rage in the late 60’s/early 70’s, what with C, S, & N and The Band leading the way), they became, and I’m not being hyperbolic, unlistenable to me. American Beauty is painful to listen to, the singing is so bad. The band I’m in now does "Friend Of The Devil", but the two singers are on key!
Here's an illuminating comparison, for those who don't object to that kind of thing: Listen to the live Dylan album with The Band as his band (Before The Flood), then that of him live with The Dead (Dylan & The Dead). Huge difference. Are they just different in kind, or is one just a lot better of a band? I have my opinion.