[Scrapdog2grand]

I'll go with the road crown theory, or perhaps a combination of the 2 theories.
you are putting about twice the mileage on the left side, and when my new tires worn the painted lines off of them, the left side went first. A lot of staight roads here for the most part though. my ride to work consist of all straight runs with 3 turns at the cross roads.
when the wife I are out cruising the turns we encounter on most high ways or back roads are very subtle.
right handed turns are sharper, more lean in the right handed turn, and the road crown makes it easier on the tires and the person riding the bike in a right hand turn.
road crown is going to cause less wear on on the right side of a tire, its aiding you in the turn, not working against you, almost all of our roads here have crown from the center line down.
and how about those roundabouts, I have to hit a roundabout in any direction I go. you can only take those on your left side(eh John?) and they are also crowned down from the center.
whats a roundabout? oh sorry, most of you dont even have roundabouts!