to me he does have a "sound" as a producer that's not just "what the band sounds like." real transiently strong sounding drums that are also wide and roomy (lots of condensers on drums even the close mics), guitars that are really grindy and sometimes very aggressive. there seems to be a lot of dirty bass too, somehow. and screamed vocals even, somehow. room mics on most vocals. and of course the minimal use of compression and reverb as already noted. I used to think I had a pretty light touch as a recording engineer but then I went back and listened to some of my recordings I did for people and thought, "wow, a lot of that really sounds like me." There's subtle and not so subtle ways this is manifested--despite any effort towards transparency, or defiant (Albini) claims to such. And deciding not to do anything is still a decision, as it were.