AT TDIclub forum, there is a thread about WVO filtering. This guy filters it like your supposed to, but adds 5 cups of baking soda to 45 gallons in a conical tank.
He then siphons the finished product off the top, and then drains the fat and gunk from the bottom of the conical tank. He has done this for 122,000miles on a 05 Jetta tdi and the engine is clean as a whistle inside.
I always thought that getting the glycerine and other impurities out meant having to use lye and methanol?!