I do really know exactly just what the "sizing" is but removing it makes the material softer and wraps around the ball better I think? I have shot them both ways and never really did see much difference. It appears to me that the Teflon coated material that you can buy is simply sprayed over material that has not been washed. Just my opinion and I might be wrong about that. Try it both ways and see? And report back curious minds want to know?

RB