oil catch tanks again

[vincevtr]

I don't know enough about engines and that's why I'm asking this. I've read through threads about these - so understand breather pipe sends oil and water vapour back to combustion chamber for emissions reasons. But wld oil vapour have a plus side - i.e. it lubricates valves etc?? In which case wld fitting a catch tank or breather do as much harm as good to anything other than a racing engine?

[Toad]

Nope, it's a pain for sure. It causes clogging in areas where you don't want. That's that then really! ;)