I saw him some years ago on a bill with Big Brother and the Holding Company and Jefferson Starship.
I was offered a free ticket, which is why I went. Everybody that I saw at the show that I knew was in the same boat. I remember thinking that was odd, but whatever, I was about to see some legends. The room was about half way full and the lights were kept up during Havens opening set because they assumed more people would be showing up, which they didn't. I don't know if he was having an off day or just a combination of factors, but it was painful to watch.
A few years later I met the promoter who put that bill together. He was driving for Uber and stopped to talk to me because he saw me loading gear into my car. He tried to razzle dazzle me with who he knew, connections etc, and mentioned the fact that he put that particular show together. I told him I was there and it looked like a cluster fuck. I was kind of impressed with how many excuses he was able to rattle off to explain why it wasn't his fault.
Looking back, dealing with that guy is probably what had Havens in a mood, well that and opening for what amounted to a Janis Joplin tribute band.