I was friends with his music director and saw a few shows a few years back in Vegas. He has quite an entertaining show, most of the people there were over 70. The band was indeed very good. Tom and artists like him know that the fans must be impressed with the band as well as the artist. Many artists work like this, its their show and they hire a Music Director to hire a band- play the parts as written.
If an artist doesn’t dig someone in the band for any reason, the music director will change people out, hires a new drummer or whatever to make his boss happy. If the artist gets unhappy about the Music Director, the artist fires the MD and the entire band is fired too. A new Music Director is hired and new band is recruited by them to their liking. They must to learn all the parts verbatim and most fans would never know the entire band was changed out.
Brad