waste of time, can't be done on that engine anyway
why waste of time Fred ?
Okay , it might not be possible on a 1,2 engine , but when looking at the TB of the 172, nearly all the mess+guck in there (eventually breaking it when not cleaned regularly) , is from the crankcase breather-tube ? When fitting such a filter you wo'nt get any oil-guck-mess in the TB i'm thinking...
Renault have designed it like this to not spill oil into atmosphere/onto the road, environmental reasons ?
Mind that with such a breather-filter your enginebay will be a bit smelly, can be nausiating