In previous books, I was under the impression that Sorilea was on about the same level as Morgase; technically able to channel, but not really able to do much. However, like you pointed out, Cadsuane thought Sorilea was capable. It also makes me think of Aviendha's ability to unravel weaves. I'm starting to wonder if Aviendha learned that skill from Sorilea. I don't remember much about Aviendha's ability to unravel weaves, but I think that this is worth looking into.

Hmmmm...

Also, if I remember correctly, didn't Sorilea have a significant choice in which captured AS were brought in to swear fealty to Rand (the group that included Elza)?

Sorry if this seems a bit disconnected. I'm just trying to piece bits and parts together.

The more I think about it, the more and more I like this theory. There's not very much evidence, true, and not many people are going to support it, but it might make it to the top of my "crazy theories" list. But who knows? I supported the idea that Verin was either BA or had somehow managed to sidestep the oaths despite little support for that theory. Maybe this will be the same.