As to why it’s relevant despite La Sarthe chicaneless, I would say that:
a) the sheer length of the straights at Route X
b) the perfectly smooth, flat, even surface
and c) the meter markers along the straights
are what elevates this track to a space which can scientifically (at least in the game) be used to show research into the physics, car performance, etc. with no ‘noise’ or uncontrolled variables which plague places like La Sarthe, and even the front stretch of Fuji.
It is the Complex String of straight line performance, and while you can argue that other tracks may be able to nearly substitute, I claim that it’s absolute perfection in narrowing down variables proves it’s worth.
Keep in mind that the conditions of Route X are SO perfect, that in GT6 we were able to prove changes to camber as speed increased, changes to ride height as speed increased, and even proved that the TEMPERATURE (and therefore) DENSITY OF AIR had a CLEAR and NOTICEABLE effect on top speed by using the sanitized Route X as a test bed.[/COLOR][/B]