Originally Posted by Eldrik
What about straight hoses? This isn't an answer, its a question.
<snip> Is the trick to have air going into one valve cover and out the other?
Straight hoses would be like creating a large vacuum leak.
From the standpoint of the engine, all you're trying to do is get the blow by out of the crankcase without blowing a gasket or blowing oil out a seal. All engines are going to have some blowby when cylinder pressures get high (WOT).
From an emissions standpoint, you'd like to burn that vapor.
The PCV valve also acts as an orifice to limit the size of the vacuum leak you're creating. It's called "positive crankcase ventilation", but you don't really want to be sucking air in through the breather cap (that's what you'll be doing at idle, if you're not careful where you tap vacuum), and you don't really want to be blowing off the vapor (but that's what you're doing at WOT because you don't have any vacuum then anyway, that's when you might want to dump it in the air cleaner)...
It's supposed to be a balance at highway speeds.
If you ever notice your dipstick (or PCV) is no longer seated after "enthusiastic" application of the throttle, you probably need some more ventilation (or you've got a broken ring, etc). Else you're liable to cause a leak, most likely at a valve cover or the front or back of the intake (PITA).