In CoT chapter 21 A Mark, Alviarin is using a red rod ter'angreal to summon Mesaaana. She is about to use the OP to activate it and thinks:

"That would not have been necessary in the Age of Legends, but something called the "standing flows" no longer existed. A World where almost any ter'angreal could be used by people unable to channel seemed beyond comprehension. Why had it been allowed?"

I don't remember reading this on previous rereads of the books, and I haven't found anything about it in any theories (of course that doesn't mean it isn't there).

So, I was wondering if anyone knows what standing flows were that allowed non-channelers to use ter'angreals in the AoL. Flows would equate weaves, I would think; so were there just OP weaves available in the air or somewhere for others to use? And why do they no longer exist?

Any thoughts?