Interesting cold weather bar tape approach. But are you sure the stuff is polypro. 98% of jackets are made from polyester. While the fiber doesn't absorb much water the weave will. But it should also dry out and with the regular bar tape beneath it should protect the bar from any moisture problems.
Also, I don't believe that any of the bar tapes are made from open cell foam. This stuff is like a sponge so no one makes bar tape out of open cell. Have only seen people use closed cell foam for bar padding which will absorb even less moisture than the poly jacket stuff.
Still it was an interesting approach to a problem and since you can buy a yard or so of scrap polyester fleece at a fabric store for probably 5-6 dollars could be a useful winter method.