I decided to try this out from the Undaunted line, as my dunmer character is based on a drow rp character of mine and, well, spider webs. But unfortunately, it doesn't seem to be doing anything at all. I fling some webs at them, and there's a splotch on the ground, but the enemies don't seem to be affected at all.
Rune Fell- Dunmer Mag Sorcerer (DC)~The Adventurer
Runed Claws- Khajiit Stam Dragonknight (DC) ~The Tank
Rain Fell- Argonian Mag Templar (EP)~ The Healer
Dragon Talon- Bosmer Stam Nightblade (AD) ~ The DPS