Never played Elite, but I got to see Dave Braben do a post-mortem of the development of it at GDC many years ago. It was super interesting hearing about some of the optimisations they were doing to make it work.

The talk is online; if you're interested in old school video games it's worth a look: https://www.gdcvault.com/play/1014628/Classic-Game-Postmorte...