I only mention the stretching of fabric at all because some folks at the hammock forum have picked up bargain fabric that isn't labeled well and found it turns out to be something that sags and stretches infinitely, or just rips right through the first time they sit in it. I'm experimenting with a heavy 10mm silk for a summer hammock but very aware that it may be too light to see a lot of use.
"In the beginner's mind there are many possibilities. In the expert's mind there are few." Shunryu Suzuki