When I replaced my CCV hose assembly (cracked hose) I cut the corrugated tubes from the OEM fittings (old hose). i installed clear hoses (Home Depot) with inline brass filters (Carquest #86050) to see exactly how much oil was heading for the intake. At startup (high vacuum) it was about a tablespoon each side. When the vaccum settled, the oil in the clear hose was allowed to drain back to the valve cover (oil never made it to the intake). The corrugated OEM tube assemblies trap oil and act like a bucket brigade to the intake.