That's the downside of forcing.

The Aes Sedai have always been much more cautious about their numbers. There are always so few channelers, and they would rather wait an extra 5 years to raise a new initiate than have her be burned out.





Oddly enough, it seems that the Seancean have the best training regimin. They're constantly being used to their fullest potential, but the a'dam prevents them over-drawing the Power.

This hearkens back to when Asmodean was trying to teach Rand to channel, and said it was a shame that they didn't have a female channeler to link them. This implies that linking is an effective way to train someone, which makes sense if you think about it. They get the benefits of constant channeling,without the risks of burning out.