When a woman like Reanne looks at Nynaeve and can feel a strength difference between her and another woman that is equivalent to 100% of Daigian's strength Reanne is going to see that as a pretty massive gap (that gap would be close to 50% of Reanne's total strength). But from the reverse side of it that's likely only about 20% of Nynaeve's total strength ... Reanne's comment about Alivia comes to mind ... Nynaeve's current strength could have been within 5% of Alivia's but from Reanne's perspective that felt like a "considerable" difference, when in reality they aren't all that far apart at all.

It's possible that a 5% difference in their raw strengths is equivalent to the total strength of a woman like Alise, so from the perspective of someone less than 3x Alise's strength that seems like a pretty big gap.

I assume the difference between Egwene and Nynaeve is about the raw strength of Daigian, which would certainly seem like a significant increase in the eyes of an AS, but in reality isn't as huge from the opposite perspective.