I just played Descente aux Enfers for the first time, and I kept thinking that this score is very much like Body Heat, so much so that it sounds more like Body Heat than any other John Barry score.
A different kind of score from the delerue I know, and I'm anxious to play it again.
I bought Descente aux enfers (1986) score nearly 7 years ago based on having a couple of tracks from a compilation but have played it only two or three times ... I can't say I've ever thought of Body Heat (1981) when I did play it.
I have bought multiple copies of the Barry score over the last 40 years and know it well ... so when I do next play the Delerue one I will consider your observation. On my geek list I see it's not due a play for another 11 months ...