oil consumpotion

If I dont connect the pcv to the carb the crankcase evaporate in the enviroment. Or is the vacuum in the manifold that much necessary?

so, today I changed the oil. It doesn't smells like fuel or exhaust gas and looked normal. (same for the coolant water in the radiator)
But my friends must be blind or the engine doesn't smoke under load. The exhaust gas I saw today in my garage was light gray with a touch of blue.
And exhaust gas came thru the oil filler hole (not that much but noticeable, passenger side) but not thru the pvc valve (filler hole closed) and thru the
breather (driver side, much more). On my way back home I monitored the (mech.) oil pressure gauge and noticed
that the pressure is at normal 55psi (all rpms) and when I accelerate it goes a lil up and when I slow down it goes down (40psi).
As that happend last weekend and the pressure dropped to 30psi I noticed the lost of oil, filled up and it was ok for a while since it happend again (200mls later).
This symptome occured first time last year during the first 500miles than never again (55psi all the time) and now 3000miles later right after that broken radiator hose.
Maybe it was a pure chance that both happend the same time. Maybe not...
Ok, next step is pressure testing. To see if the rings are down I put a bit oil in the cylinder and check a second time. If there is no difference the rings are ok. Right? How do I check the valve stem seals (umbrella type) and head gasket without disassemble the hole engine?