1. Try your hypothesis, see if it actually works. This debate will go on forever. Keep in mind that crankcase ventilation improves oil and bearing life; you may not have full results of your modification unless you do oil sampling on a regular basis, and the bearings may not show problems for a hundred-thousand miles. 2. Study what propane/LPG forklifts or other industrial engine designers are using to "fix" this problem. 3. Contact the folks who made your gas mixing valve, see what they recommend.