Im no expert but here's my .02...
1. I think the greatest evidence of how the driver makes the 'final' difference is shown by the 4 second difference in the same car with the same points while driven by Steve G.
2. When adding points to get to the Stock, Improved and modified classes, generally, these people have driven in a stock class for a while and are now improving their car. They are feeling what the car needs to go a bit faster, shocks/springs/sway bars etc.
As an example I run my car in AM and have I think 42 points when I run 9's in the rear and race compound (kumho) tires. I can have up to 54 points in AM, but, I still do well in the class. If I could knock 10 seconds off my time by adding 10 points I'd do it.
So in my opinion there is no correlation between the two simply because there are way too many factors involved.