We need to reconcile these first two facts with the (seemingly) contradictory third:
1. that there are 21 levels of OP strength, and their distribution follows a bell curve,
2. that Nynaeve is at the level of most female Forsaken, and Egwene, Elayne, and Avi are one level below her (See quote below), and
3. that Nynaeve would be like a bonfire to Egwene's candle (or some such wording).

What we're looking at is two different things: the levels, which according to RJ are distributed on a bell curve, and the strength associated with a level (which I will call the "strength function" ). Through the discussion so far, the assumption has been (implicitly) that the strength function is linear.

However, if the strength function is linear, then the facts I gave above make no sense. If Eg. and El. are one level below Nyn. then the difference in their strength would be the same difference between any other two levels. It would not be notably different. Therefore I propose that the relationship between level and strength cannot be linear.

Kieran has proposed that the strength function is quadratic, or strength=(level)^2. Let us investigate the implications. Let's say Nyn. is at level 20, and Eg. and El. are at level 19. If the strength function is quadratic, then Nyn. would have strength 400 and Eg. and El. would have strength 361. Thus, even though the levels are off by only 1, Nynaeve is more than 10% stronger than Egwene and Elayne. Is that enough difference to inspire fact 3 above? Maybe, maybe not. (I also point out that Nynaeve at level 20 would be 3 times stronger than an average channeler at level 10.)

At this point there isn't any evidence in favor of this particular strength function. Perhaps someone could ask BS at a signing what the strength function is or how it works. However, given what we know, I think that no matter what the actual strength function is (quadratic, some other polynomial, maybe exponential, etc.) it almost certainly is not linear.


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I found this quote from the link at the bottom. To find it do a ctrl+F and search "Stockholm"
Quote:
On channeler strength: he said that he knew the rough strength of every channeler in the books, imposed on a 21-graded scale. Nynaeve he said had Forsaken strength, i.e. as strong as most female Forsaken. Egwene, Elayne and Aviendha were a step lower, and an additional step lower Elaida, Siuan and Moiraine were found. They were the strongest Aes Sedai known before "the new ones". Several Aes Sedai, including Leane and Kiruna, were next in strength. By the old standards they were deemed very strong and capable. [RJ apparently forgot (or maybe the person doing the report mixed it up) that there is a level between the Supergirls and Elaida/Siuan/Moiraine/Romanda/Lelaine - Cadsuane, Kerene, and Meilyn are stronger than Moiraine's group but weaker than Egwene's group (New Spring). It's also worth adding that Sharina is predicted to become as strong as it is possible to be (like Lanfear was, apparently), and Talaan (along with maybe Alivia) is probably between Sharina and Nynaeve, so that makes at least two levels, maybe three, between Nynaeve and the top. - Terez]