The whole book is written to reflect the knowledge of fictitious 3rd Age scholars.

It's canon, it's accurate... only so far as the information from the series is, ie: unless assumptions are proven to be misinterpretations or plain wrong.

I'm not saying Ishamael isn't a match in raw strength for LTT, I'm merely saying we can't be sure of this is the right way to interpret the scraps from the AOL that appear to say this, and short of a direct quote stating this from one of the Forsaken or Rand, we'll never be sure.

There's this nagging problem you see that Ishamael stood above the other Chosen and had the same power over the Shadow LTT had.

And there's the problem that Demandred happens to have been second in the Guild to only LTT.

That opens the door wide that the quotes referring to their OP strengths aren't about their strength the way AS scholars interpret them, but about their global power.

The Forsaken almost never refer to their comparative raw strengths, if you noticed. They don't think like Third Age channelers.

I think you're wrong about Aginor. We know he used the OP/TP in his work, it's very clear it's fundamentally OP related work. He refers vaguely to the challenge making the Shadowspawn represented in LOC.

That may be his only true Talent, but it was amazing.

I'm not convinced about Demandred/LTT. Both have not demonstrated any outstanding Talent, nor referred to them. It's especially suspicious in the case of Demandred as you'd hardly expect humility from him in his POV (or for that matter from LTT).

Lanfear is totally biased when she speaks of LTT.