The fact is that for every Sharina who has no interest in the Tower and who is therefore missed out, there will be a corresponding Verin and Dagian and Sorilea level channeler who is also randomly missed out.

Therefore, even if the Tower only finds 1% of all channelers, this 1% is a random distribution of the entire channeling spectrum. Random, except for the 37.5% weakest level channelers who are DELIBERATELY excluded.

There is no reason why more strong women than weak women would be missed out on this random basis that you are proposing.

Aes Sedai come from every nation in Randland, and would include equal numbers of strong and weak channelers. If no selection policy existed, they should be very close to a perfectly representative sample of the entire continent's channeling population.

There is no reason whatsoever that only women around the 50% mark or weaker should arrive at Tar Valon. None whatsoever.

So if there are 99% of channelers still out there, then they should have the same strength distribution as the Aes Sedai in the Tower. Except that the Tower selection is skewed to the stronger side, due to the 37.5% that are deliberately excluded, and thus moving the Aes Sedai mean strength higher than the mean strength of the general population.

Statistically, there is no way around this.

For every Sharina that is never tested, there is also a Morgase that is never tested. Because they are missed randomly, and not through a policy of deliberate exclusion.

The only factor that will skew the Aes Sedai sample, is the deliberate exclusion of the weakest 37.5% of women.

This is proven by the fact that only 12.5% of ALL channelers fall between Dagian and the average woman's strength.