I have a quick question and I understand gates starts functioning when you get the "confident" echoes. What confuses the hell out of me is you keep getting this echo. In regards to AC

AC pierce : PPP AC bash : BBB
AC slash : SSS AC magic : MMM
AC element: EEE

Does this mean each separate "AC class" need to reach the AC threshold and hence the multiple echoes. Or is there some wierd across the board maths that once you reach a total level across all five AC classes that gates just turns on and the extra echos are simply a "Wow look at you MR AC type flair?"

Yeah that sums up my experiences and adds weight to my thoughts that AC like this

AC pierce : -1000 AC bash : 100
AC slash : 100 AC magic : 100
AC element: 100

Effectively means gates is taking care of pierce damage only.

The echo fires anytime you wear gear and you are getting a bonus to gates.

Yes it appears gates cares about your AC vs the relative type. At least I noticed a difference against magical types of damage when that AC was way lower than the physical types.

What matters most is gear with -ac on the identify. I wanna say things like bracers of defense, perhaps polished mithril girth, I think there are a few cloaks with -ac. Anyways there's tons of stuff out there.

That seemed to matter far more than heavy armor or whatever things you're thinking about.