Rolling resistance: Tyre diameter vs width...

[CommodAnt]

Hi guys,
I'm looking at filling up the wheel arches on my ride to not only make it look better, but to fill the void surrounding the wheel which has got to be hurting fuel economy. I would ideally like to maintain the same level of traction from the vehicle (it still needs to stop and handle well), but overcome these aforementioned issues.

It is generally accepted that a larger diameter wheel is good for fuel economy due to lower rotating speeds within the drivetrain and wheel bearings leading to less friction, but bad for acceleration due to the associated gearing changes. I am assuming that due to the larger rims having a larger contact patch with the road that this would increase rolling resistance from the tire itself?

If this is the case, then why not fit larger diameter wheels (+2 in) with a narrower profile (-1/2 in) to get a comparable contact patch with the road, and decrease all other friction processes internal to the vehicle (assuming I'd already done the calculations - which I haven't).

Am I missing something here or does this seem like common sense that has been overlooked? Please discuss.