Someone just edited the page to remove the reference to joint making not increasing any skill, without any comment. Can someone confirm that it does indeed train its associated skill (Cooking)?
I've already modded my install to have joints be made at the campfire and stoves and thus use the Cooking work tab (and it does increase the Cooking skill), but with dirty direct XML editing, so I don't want to risk messing things up trying to get it back to vanilla just to test this.