I have 2 comments related to this.
1) As much as I liked Chuck Mangione music back in the late 70s & early 80s, I came to the conclusion after listening to a bunch of his albums that Chuck seemed to have only 3 or 4 melodies in his head, and all of his tunes were just variatioins on those themes.
B) In our family music store, we used to sell records (was great for digging up those older MF albums back in the day). A perennial big seller was Andy Williams. Why? you might ask - all his music sounded the same. Right on. An Andy Williams fan knew exactly what they were going to get on his new album and was never going to be unpleasantly surprised.