I saw lukeprog's signing messages as minor noise and possibly a finger macro developed long ago, so I stopped seeing the signature.

I'd be dubious about assuming one can be certain (where's the Bayesianism?) about what someone else is intending to signal, especially considering that it's doctrine here that one can't be certain of even one's own motivations. How much less certain should one be about other people's?

I would add some further uncertainty if one feels very sure about the motivation driving a behavior that's annoying.