Is it normal for the outside edges of the front tires to be stairstepping
on the outer inch or two only?

By stairstepping, I mean that you can't see the wear all that much but if
you rub your hand over the tread in one direction, you can feel a lip on
each side swipe tread.

If you run your hand over in the other direction, you don't feel it. You
only feel it if you run your hand from back to front on the outside tread
of the two front tires.

If you do the same with the rear tires or on the inner edge of the front
tires, you don't feel any 'stairstepping".

The tires are about a year old and are wearing the front outside edges
only.