For giggles, I pulled off the PCV side hose at the intake manifold on my FiST the other day and found oil in it. Am I worried? A little. Would a catch can help mitigate the risk somewhat? Possibly, it depends on what oil is used, but catch cans aren't 100% efficient either. Oil entered in to the system via the PCV is only a small part of the equation. VW/Audi FSIs and TSIs have a built-in air/oil separator, not just a simple PCV valve. Those guys generally just catch water/fuel vapor in their catch cans, but yet they have an extremely high occurrence of carbon issues. Looking at the FiST PCV, it's just a PCV valve and a hose to the intake manifold.
Oil will still exist in the intake ports even with a catch can. Look at the nature of how valve seals work. While the seals are supposed to keep oil from dripping in to the ports, a certain amount has to get by to lubricate the guides. This oil runs down the stem and in to the intake port. It's not as much as the PCV adds to the intake system, but it's enough. See the mushroom of oil around this valve stem in this pic? That's the oil coming from the valve guides.
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In the US, generally every oil available would be considered "high SAPS." In this country, no one seems to care like they do in Europe.