You made me really happy with this comment. Tron was a big movie for me in my youth and a big reason why I was drawn to computers and ultimately programming. I also came to love synth and electronic music (Art of Noise etc.) around the same time and have always thought the Tron soundtrack to be amazing, especially the credits track. But I know nothing about music theory, I'm just glad it's good music. Thanks.

I heard as an aside that the London Philharmonic parts of the soundtrack were commissioned and recorded because Disney didn't have confidence that Carlos would finish her work on time (or at all, the relationship was a little strained), and using both was a decision made only afterwards.