That was also mentioned over in the Busse s/f on BladeForums, and I noticed too. I would attribute it to manufacturing tolerance.

All you would need to get that kind of difference per side is a change in the direction perpindicular to the blade of about 0.015" while making the cuts for the primary grind. That's not much, and I can see that easily being the case.

Say, for example, they have 500 blade blanks to grind. They chuck all of them up in the CNC machine and cut one side. They then change the tooling in the machine to cut the other side, and proceed. Say the bit moves slightly, is changed, or dulls down a bit, etc. There's your 0.015" difference. It's really something more along the lines of +/- 0.007". Even smaller.

Of the pair that I received, one is asymmetric like this, while the other is not. On the symmetric one, there is about 0.55" of flat to the edge of the primary grind, so it about splits the difference.