I am a diesel mechanic, so I know a bit about diesel crankcase breather systems. Until 2007, all truck diesels simply vented the breather to the atmostphere. That's quite ridiculous, when you think about it....EPA focused so hard on tailpipe emissions yet chose to ingore the oily mess left on the ground under every single truck. However, in 2007, every manufacturer was required to install coelescent breather filters on their engines. Small engines (below 300 HP or so) required CCV, which simply routes gasses to the turbo inlet much like our TDIs. Larger engines still retain the open ventilation, but with the addition of this filter.
The filter has a breather inlet, outlet, and an oil outlet which goes back to the sump (oil pan). The filter assembly itself is approx 10" high, 8" wide, 3" thick, and is good for a 600HP diesel engine for 60,000 miles. From what I have seen, these filters do a remarkeable job of not letting any oil get through. They have a replaceable filter element that causes the oil vapor to liquify and split apart from the gasses, allowing the oil to drain back to the engine.
Now for the point. I am quite sure that these units are readily available for smaller applications, aka TDIs. They would work sweet, but probably at a slightly higher cost. There would be absolutely no freezing or plugging up to worry about, as long as you changed the filter every 4 oil changes, which is what the interval for HD engine is.
James