I prolly won't try to re-use any of the oil caught by the canister. It'll contain a lot of gunk that tends to accumulate on top of the baffle inside the valve cover.
So far there's been no appreciable accumulation (just enough to 'wet' the plug on the bottom of the canister).
I'm thinking about modifying mine slightly: Add a drop tube to the inlet so that those gasses come into the canister about 1/2 way down. Add steel wool or sump'n to act as a baffle to condensate more of the liquids before going into the combustion chamber. Haven't quite convinced meself that it's needed yet. Since I've gotten so little accumulation, I think it's worth a shot.
BTW, with mine bolted to the airbox, there's little access to the drain port on the bottom of the canister. If I were accumulating enough that it needed to be emptied very often, I'd prolly relocate it so that the drain was more accessable.