I just had this thought and was wondering if anyone has set up their suspension with negative camber(top of tires tilted in) in order to reduce contact patch and rolling resistance. I dont see why this wouldnt work, but I dont know if the gains would be measurable. The negative camber would have to be offset with a small amount of toe out to negate the tires tendency to roll towards each other when they are tilted. This would help traction on hard cornering enabling one to hold speed better, especially on a car with lots of body roll. Braking would be slightly hindered. I imagine this would enable you to effectively lower rolling resistance while increasing cornering capability.
I don't see how it would work to reduce rolling resistance... after reading the materials I found on tire rolling resistance and accepting their premise that sidewall flexure causes most of it, it looks to me like anything other than 0 camber would cause increased sidewall flexing and the tread is still likely mostly flat to the road so...
But it does make sense to me how it can improve cornering capability.
Godyear says that the TREAD causes most of the rolling resistance.
If the tires are overinflated enough to prevent the majority of sidewall flex though, it might help slightly. I saw a picture of a pickup truck on two wheels with 100 psi front and back, and the tires held their shape. There was very little flex and the wheels were still rectangular when looking at it from the front. I think that it's in the same police article that was about the safety benefits of overinflation.