For 99% of mud the catch can routing for the PCV is fine, but if you have forced induction you have to reroute your PCV. If you think about a naturally aspirated engine with the port in the intake manifold it will ONLY draw a vacuum on the PCV sucking excess crank pressure out of the PCV into the intake, but if you boost your engine you now have boost/positive pressure in your intake manifold blowing into your PCV hose. Best case scenario is now your PCV doesn't work at all, worst case you pressurize your crank case and blow out your seals.