One of the very best things about living in Kansas City since 1982 was the opportunity to see Jay McShann perform live more than 25 times, in small group, duet, and big band settings. I saw him perform in duet with Marian McPartland, and in small groups with a variety of guest musicians, including Buddy Tate, Harry "Sweets" Edison, Claude "Fiddler" Williams, Harold Ashby, Red Holloway, Plas Johnson, Duke Robillard, Myra Taylor, and many more.
Jay McShann sang in each of the many live performances I witnessed. He often sang a verse to "Hootie's Ignorant Oil" which was not on the original recordings.
I like his singing on the 1970s Columbia album "The Last of the Blue Devils" (not a soundtrack of the film of the same name). To me, he steals that film--he is on fire in his performances in that film.