The one question I would pose on this issue was briefly raised before and refers to the test for saidin. Given the scarcity of male wielders of the Power it's unreasonable to suggest that such a test could be discovered by random experimentation. You would need to have either a) a solid theory of how the power works (which even in the Age of Legends wasn't completely understood, hence the Forsaken's surprise at Warders) or b) another saidin channeler and a lot of experimentation. So, the question is who taught Taim the test? Either he's a Darkfriend or he really is Demandred, but he is not just Taim.
wotmania says: Darn that stupid test... It is one of the biggest holes in my idea that Taim really is not Demandred. I have no idea how Taim could have (reasonably) learned about the test... Any ideas out there?
I have no clue how Taim learned the test, but that doesn't mean he couldn't do it... after all Nyn 'learned' to heal stilling (something that couldn't be done), Egwene was learning to be a dreamer before the wise ones taught her, Rand learned some channelling before LTT started talking, etc, etc, etc. Everyone in these darned books is learning something new

Why not Taim?
Aside from teaching Rand the Saidin test Taim also was the one to teach Rand the Aes Sedai trick of ignoring heat or cold. It is unlikely Aes Sedai taught him or that he just figured it out. I also can't see one of the Forsaken teaching it to him if he is a Darkfriend, why would they
Yes, but healing Stilling was something she was trying very hard to do, with 3 people to study, and she had an idea of what to do. Do you think Taim just randomly stumbled into having someone concentrate on a flame (or whatever the test was) for up to 10 minutes and knowing that what he felt meant they could channel? I don't think he is Demandred, but I do think he's a darkfriend.
KLitke7967
It is true that Corlan Dashiva spends most of his time with Rand before betraying him, but I cannot think that Taim (if he were Damandred) would work in concert with him. Also, in Far Madding, Kisman reflects that the M'Hael, Damandred, and Moridin all order him to kill Rand as if they do not know about each other's orders. Of course, that could be a ruse, but why bother? It seems likely that Osan'gar or Damandred have been teaching Taim (since only a darkfriend would want Rand killed?).
the test