Yeah, I don't know what to refer to this glitch as, so if there's an actual name for it, please let me know so I can better convey what I'm talking about here. I'm sure it's been reported before. I don't care. It hasn't been fixed.
https://www.youtube.com/watch?v=t0TY8DOKAjo
This is the glitch in action. Dragonknights, Werewolves, and Dawnbreakers know it well. It's been around since launch and, since the recent patch, it's not extended to many other abilities. This is a serious problem, especially for serious content, and compounds the more players you're running with. In more difficult group content, the more people you need, the more you depend on to be able to perform their role. When they're stuck unable to do something, they're a sitting duck, and you have to make due without them indefinitely (it usually works itself out after a minute or two, but sometimes it just doesn't).
Please, please, PLEASE fix this, ZOS!