Well, thanks all, for the research and discussion. I did get the chance to check out another set of identical tires on a Jeep, fairly new, and noticed the same thing. This seems to jibe with most of what I heard elsewhere, i.e. it appears to be common with this make and model. The tread wear is even and the tires behave on the road after balancing. At least I can be easy in my mind when I next go out. However, I wouldn't mind going for heavier construction (more plys) on my next tire replacement. Too bad there's not a heavier version of the AT. The MTs are not what i want as far as tread goes.