Probably true, but maybe a hint from a Sanderson interview should be considered here... - Edit 1
Before modification by Shannow at 26/09/2012 08:57:58 AM
We pretty much know which "agents" Moghedien is talking about, as we know when she discovered Nynaeve's existence.
She must have asked someone in Liandrin's group (and that this is the explanation is supported by the fact Moghedien's "agents" aren't in the Tower where they'd have spotted Sharina for instance). Liandrin's group must told her about the Tower's strongest women, it's even likely it happened after Moghedien saw Nynaeve's strength for herself (it's her, not the BA who found Nynaeve in Tanchico), so much above those of those BA. That must be what sparked her curiosity - for her own safety she had to know if she'd encounter many more like Nynaeve. She must have asked the BA if there were other AS like Nyaneve or stronger.
Basically, that quote just tells us Moghedien found Hessalam to be of significant strength. It also pretty much tells us Graendal was strong, but not in the "freak" zone like Lanfear because Moghedien wasn't surprised enough for that, nor did she think of Graendal's strength.
IMO it tells us Graendal is either in Nynaeve's range or somewhat stronger, but still in the zone of strength that's rare but not exceptional enough for her to think "wow, this woman is exceptionally strong, about as strong as Graendal". If Moghedien met someone else of Lanfear's strength, it's something like that she would think.
She must have asked someone in Liandrin's group (and that this is the explanation is supported by the fact Moghedien's "agents" aren't in the Tower where they'd have spotted Sharina for instance). Liandrin's group must told her about the Tower's strongest women, it's even likely it happened after Moghedien saw Nynaeve's strength for herself (it's her, not the BA who found Nynaeve in Tanchico), so much above those of those BA. That must be what sparked her curiosity - for her own safety she had to know if she'd encounter many more like Nynaeve. She must have asked the BA if there were other AS like Nyaneve or stronger.
Basically, that quote just tells us Moghedien found Hessalam to be of significant strength. It also pretty much tells us Graendal was strong, but not in the "freak" zone like Lanfear because Moghedien wasn't surprised enough for that, nor did she think of Graendal's strength.
IMO it tells us Graendal is either in Nynaeve's range or somewhat stronger, but still in the zone of strength that's rare but not exceptional enough for her to think "wow, this woman is exceptionally strong, about as strong as Graendal". If Moghedien met someone else of Lanfear's strength, it's something like that she would think.
I'm always on the lookout for strength comparisons but I found this one pretty uninformative. I merely assumed that it pointed to Nynaeve and Hessalam being stronger than Moghedien but neither of those two are a surprise, and we know that even Cyndane is stronger than Hessalam. I don't think Moghedien's quote form the basis of even the weakest theory. Its like Daigian commenting on an Aes Sedai who is stronger than her.
When Sanderson was asked how Nynaeve's strength compared to Semirhage, he went into how Nynaeve is incredibly strong (with only 6 females stronger than her). He then said that Nynaeve's strength is so rare that whenever we encounter someone stronger than her, it will pretty much be remarked upon.
Well, I find it quite interesting that Moghedien brings Nynaeve's name into her totally unrelated thoughts on Hessalam's strength, and saying how it is unbelievable that Hessalam wasn't noticed by her agents if Nynaeve was.
This could be Sanderson staying true to his comment that anyone who is stronger than Nynaeve will be remarked upon with a comparison to Nynaeve in some way.
In any case, this certainly links nicely to previous estimates of Graendal being stronger than Nynaeve, and the fact that Graendal really has to be one of the 6 channelers above Nynaeve, if Semirhage isn't one of them (he still left that open to a slight possibility).
Nothing conclusive, but it does fit the generally accepted picture.