I would get quite a bit of oil out of the crankcase auto- X ing and at track days. It got so bad it would get on the MAF housing and on the hot wires of the MAF itself!
My setup is all motor and close to SPEC as i am practicing HPDEs to hopefully run the series. As you can see my crankcase vent is straight to the intake. that was the source of the blow by. We really need to look into this more and we might get someone in the know.
The air-water catch on my battery box is is hooked up to take from my PCV valve and send the clean gasses back to the intake manifold. after this can was put in, i dont have any problems on the Track or at hard day of test. The hose from the cranckcase is clean and i take off the MAF housing every now and then and it is clean. The only question is if the catch put less pressure on system all together or is the crankcase and PCV totally have nothing to do with each other.