You do realize that casting VS while using AG does nothing but make the mobs more pissed off at you right? Mitigation doesnt stack and the recourse just bounces. Healing yourself generates more agro rather than the oposite which ought to be the primary goal when trying to survive.
You cant compare two AA's in a vacuum. It's very significant that shaman have no way to reduce or get rid their agro when you are talking about a survivability AA. If a shaman could hit a fast cast mez /mem blur and stop being hit entierly, then sure, AG would be nicer than rune, but the fact is we can not. In order to make the best suggestions we can as to how to make AG more usefull and acceptable to all of us, we DO need to look at class balance, and the cumulative sum of our abilities to survive.
And to answer your question, yes, i've used runes in the same content as AG on an enchanter.
This isnt supposed to turn into poo flinging contest, most of us here are just trying to suggest improvements to something that as a community we've been asking to get for a very long time, and now that it's implemented falls far from the reality of what we need.