I'm trying to structure a system for rating player's performance in my arcade-style racing game. So I'm thinking about calculating the best route possible, and trying to guide the player towards the best way of driving. Is there any work into such problem? Links to papers/implementations would be awesome.
I think the easiest way is to split track in sections and measure the time in each section as performance indicator. (That they do in real racing events)
As stated here what you're asking is not an "exact science".