The membrane that is called Gore Tex was not developed for the applications it has ended up in. It does "ok" but it has limitations.
I have always been impressed with how the company was able to re-define "waterproof". Marketing genius.
Someone realized that there wasn't a hard and fast definition of "water proof" and decided to define it based on what their product needs were. Design a test that your product can pass, then define the answer.
Water proof used to mean "no water gets through". Now it means "water will not get through under this condition, and this condition and this condition."
