After rereading the Isam section of the prologue, it seems like either Brandon was confused or that you may be right about the TP. First, there is the observation about Moridin and the Samma N'Sei (Sightblinders?) that "The constraints that held them did not hold him." Then Isam thinks that he "would slip into Tel'aran'rhiod, secure in the knowledge that not even one of the Chosen could follow him from here." And, "He knew his abilities fascinated the Chosen; he could do something that they could not. Oh, they could imitate the way he stepped into the dream, but they needed channeling, gateways, time." This all suggests that Isam believes channeling in the Town is impossible. If he thought it was only forbidden, then he wouldn't think the Chosen would be unable to follow him into TAR "from here." And his first thoughts upon meeting Cyndane were that he had never seen this Chosen before, not assuming a disguise like all his previous masters had used.

BUT, he does then conclude that she is disguised. So does that mean a weave can hold, just no new channeling? And then when he faces the Samma N'Sei "He couldn't kill both of these men. He'd have been reduced to ash before he managed to take down one of them. He'd seen Samma N'Sei kill; they often did it just to explore new ways of using their powers."

So, how to resolve this apparent contradiction? How could the Samma N'Sei be unable to defend themselves against Moridin but also capable of frying Isam in the Town? How could the Chosen be unable to follow him into TAR and able to disguise themselves?

Maybe we already have some clues.

In the Town, a corrupt reflection of the rest of the world, but especially the Waste, there is the differentiation between the Talentless and the Samma N'Sei, some of whom are captured Aiel men going into the Blight, others were "the Samma N'Sei who didn't breed true washed out of their training." So we know there is training (doesn't mean it is from Moridin or anyone but other SN). We know that this Town has stood for two thousand years. We know that some (maybe most) Red Veils are born (bred) in the Town, and that those that can channel are called Samma N'Sei, Eye Blinders (or destroyers of eyes, or sight blinders?) and those that can't are called Talentless. We know that they love experimenting with new ways of killing with their power. We also know that Aiel caught in the Blight are turned against their will (and maybe these are the only ones who file their teeth?). Isam is also very reluctant to look into the eyes of the Samma N'Sei. This could mean any number of things, but one possibility is that like Ishy/Moridin, their eyes show the effects of the TP, whether as fire or Saa. It would be like staring into the eyes of the Dark One. It is maybe a perversion of the Seanchan practice of avoiding eye contact with superiors.

There is also remarkable similarity here between the Black Tower and the Town. So much so that Taim's infamous comments about "so-called Aiel," his surprising level of training, his efforts to find new ways to kill with the power, and his disdain of all weapons (the Samma N'Sei do not carry ANY weapons) makes me suspect that he spent at least some time in the Town. Maybe Taim trained there. Where else would he have had a reason to learn how to test for channeling in men?

But is the Town just an Aiel version of the BT, complete with Turned OP channelers and an army of warriors unable to channel? Or is it possible that these Dedicated, completely reliable Shadow Aiel are actually wielders of the True Power? Maybe channelling the One Power is impossible in the Town, and the Samma N'Sei are only allowed very small amounts of the True Power (while Moridin has no such restrictions).

It just seems weird to me that none of the Chosen would know or be jealous of the Samma N'Sei if they could channel the TP. Isam doesn't think it is weird that he is meeting one of the Chosen in the Town, so they must know about its existence. Or maybe it is only those coercively turned to the Shadow who are normally allowed to channel the TP. Only they can be truly trusted. They are basically slaves, while a Chosen is being honored.

If I had to guess on the assumption that Brandon was not making a mistake, it would be that channeling the OP in the Town is limited somehow, but not impossible. They can kill and burn people, but they cannot Travel or do anything too powerful. I do not think the Samma N'Sei channel the True Power. I think Taim learned a good deal from the Town, where he was safely trained in the use of the One Power for the Shadow and that he later applied a lot of what he learned to the Black Tower. Mostly, however, I am just confused and intrigued by what we've learned.

LoialT