Question about the oil separator in the air filter housing...

[DieselHead]

Greetings,
I read a thread a while back where some people were talking about how they had bought a K&N filter model RU-1000 and attached it directly to the turbo housing. It sounded like a novel idea so I went ahead about bought the filter and it came today. I plan on making a new oil separator, but for the mean time, what will happen if I attach the K&N to the turbo and bypass the original filter, but let the original oil separator keep on working? That is, what will happen if the oil separator works without any source of vacuum (originally created by the air flow in the filter housing)? I just re-read this and I'm not sure if I worded it so that it will make sense. I hope it does, I'm sure there's someone who is as scatter brained as I am who will be able to figure out what I'm trying to say. Thanks.

Alex