I just felt some elements in Grusin’s music up until 1987 that I have heard in Foster’s (like Symphony Sessions) or Howard’s material. And I don’t agree that Howard was not into jazz, he could really write some fine jazzrock in the 80s.
I didn’t mean that Howard can’t do jazz but not being familiar with his early work (besides knowing he played/arranged for Elton John) I didn’t find it obvious. Will check out Foster’s Symphony Sessions.