I was concerned about that as well! so picked up some ripstop to make a second layer. Figure I can try without and if it seems precarious I can re-whip adding the ripstop and have a double layer. And if it does rip, I can re-purpose the silk to make a pad sleeve/SPE.
"In the beginner's mind there are many possibilities. In the expert's mind there are few." Shunryu Suzukihttp://hikeandbackpack.com