Frank,
First time in over forty years I've heard someone say that nylon does not absorb water.
By aBsorb, what I mean is that the moisture enters the material and causes it to relax and stretch more and stretch easier.
Nylon fishing lines (monofilaments), aBsorb water and stretch more when wet.
Nylon fabric stretches more when it gets wet. Just ask any soldier that's ever had to get their cot set up properly...wet the fabric, it will stretch into place more easily. Same deal with nylon truck bed covers, convertable tops, etc.
Nylon threads do the same thing, at least all the ones I have do. If you think it doesn't, go ahead and test it.
Buddy
It Just Doesn't Matter....