I know logically it must be the driver who gets used to the car, but do parts, eg gears , wear according to how the driver uses them so the car does adjust, ever so slightly, to the driver, or am I stark raving mad?
Well, a lot of newer cars have adaptive learning in the automatic transmission and engine ECUs, which do indeed learn the drivers (bad) habits.
Aside from that, everyone does drive a bit differently, and on different roads, so I guess yes, in a way every component would wear differently, and two exactly the same cars with two different drivers would feel completely different (especially to the drivers of the opposed cars). Especially if one of those drivers happens to not use second gear when the gearbox is cold, and the other canes it from cold all the time, you would have a big difference in feel from that (or similar circumstances)