A byproduct of combustion, is H2O. So if your motor has blowby, you're going to get some condensation in your crankcase. if your PCV systemaint working as per factory, then it'll seep out your breathers. The only time I've had serious water build up in my catchcan, was when I had a cracked head. Blowby sucks. It's not always ideal to loop you catch can back into the intake. If you plumb it in before the Pump (turbo blower etc) you'll end up coating the inside of your intercoooler with crap. This will reduce it's efficiencey. If you plumb it in after the pump, when your on boost, (and the motor is making the most blowby) there is no vacuum to draw the vapour into the engine.