hmmm...
all of these answers sound really complex.
I'm not sure what you are speaking of. I saw some really flimsy hay nets that were made of materials that looked to me like baling twine or flimsy nylon. Quite frankly, I'm too much of a worry-wart to use something like that.
I shopped around and got a Nibble-Net for our girls. I have no affiliation with the woman who makes them, but I've been really pleased with the product. When using, I strung it up high enough so no hooves can get caught---over/around their stall bars and also on the fence. I kind of keep an eye on them when they have it. It does slow their eating down a bit. The first few times, Baby bounced it around so much that our mare freaked out. But overall, it's a nice tough product.
In the stall, it's "up against a wall." ...not too sure why that would be a bad thing?