PCV versus oil catch can and breather??

[robbo_yobbo]

I have been hacking away at the intake system lateley and ended up replacing the stock intake piping which left me with no plug for the crank breather hose at the back of the rocker cover.
This was all good as purchased an oil catch can instead and fitted a little breather filter to the lid and hooked the breather hose from the rockercover up to the catch can.

Question is though, for the sake of tidying up my engine bay can the hose at the front of the rocker cover that the PCV hooks up to be connected the the breathable catch can too without causing any issues??

If so do I have to replace the valve with just a straight through hose??

My car started some funny business when the PCV hose got disconnected once but on the other hand Ive seen other cars with the PCV running straight to a catch can before, so why does mine rev funny when its disconnected from the inlet manifold, yet other cars run fine when its hooked up to the catch can??

Cheers.