Pianist Art Tatum had the habit of staying on after the concert. When the official part was over, Tatum got really pissed (with alcohol) and it only made him play better. If we can believe the stories, those were the moments to keep.
Not so much for Tatum himself though: some months after this live recording was made, his liver gave up and he died of uremia. That is a condition where there is just too much urine in the blood. While writing about all these dying musicians, I am sure getting to know more and more typical alcohol and substance abuse afflictions!
Art Tatum is seen as one of jazz greatest piano players, and even though this style doesn’t particularly make me happy, I can distinguish quality.