At one point, Lanfear reflects that she was about as powerful as it was possible to be. Is there an upper limit to human channeling ability, some sort of asymptote that channelers approach but never pass beyond?
Yes, there is an upper limit. In terms of the channeling of raw amounts of the One Power, men can handle more than women. However, women are much more dextrous in their ability to use the One Power, so for all intents and purposes, they are equal in their abilities to do and create weaves and are mostly equal to each other.
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