There's another angle here, that pertains to the original Poster for sure.
berndt has a car with noticeably more wear in the rear, so I'd guess he might have excessive toe-in in the rear. (proper specs stickied in Wheels, Tires, Brakes & suspension)
Lived with this problem on a car I had from the 70's, NORMALLY bearable with 4 snows, but treacherous at times....
What happens is one side getting traction and tracking "straight" while the other is skidding a bit - when they alternate you get the "wiggle", and it DON'T feel good.. (grin)
Extreme version is felt on wet pavement when rear suspension bushings are worn out, leading to variable and excessive toe-in when cornering. (or toe out depending on which side is loaded/worn out)
My ZTS sedan from '04 doesn't currently exhibit this behavior, but I adjusted the alignment to the specs from this site B4 it's first winter with me.