Hey Kev,
Sorry- I should have been more clear.
Usually the exhaust spews out a ton of oil and gunk that gets all over the plane, where the case vent leaves just a little oil running back from the line.
I chimed in last week on your post about my Senior with the exhaust running to the back of the plane and the case vent tied into it.
This is the only way I know of to keep everything clean.

Kirk