Tbh I am not entirely sure that pic is correct,but to be fair its been a while since I have thought about it lol
I assume that T from the original seperater go's back to the intake pipe then tank?
If so I think its making the catch tank not as effective as the blowby from the hose in the block can just get sucked straight back into the inlet before it even makes the tank?
I don't think there is any really problem venting both from there but instead of the T I would run another fitting off the can back to the intake if you want to stay recirc.
You maybe ok as you have keep the seperater but there also should be a restrictor after the seperater really,more for track bias cars but worth noting nonetheless.
There mention of it in this thread.
http://www.gtiroc.com/forums/showthread.php?63541-Oil-starvation/page4&highlight=restrictor