I think we have to dispel the misconception that oil from the breather being recycled into the inlet causes loss of power.
It does not.YS engines do it.Oil ratio goes up and you adjust for it..If breather oil is dirty and contains dangerous impurities, then the oil is substandard or the engine has tremendous wear.
If it is the case then YS , OS, ASP, Magnum and full sized engine manufacturers should be sued for poor engineering.In fact the good thing is that residual fuel left over is recombusted and blown out thru the exhaust