It's a good test for all Green Sisters, let's say, but it's pretty off to test Greys and even more Whites and Browns, and most Yellows. Most of these women will go through their whole career without ever being faced with channelling in conditions of extreme stress like this.

This test must have deprived the Tower over the millenia of a huge number of extremely talented weavers who were just ill-equipped to deal with extreme stress, or who couldn't shut off all their emotions no matter the situation they face. Not everyone has the mental aptitudes to be a warrior, or a block of ice. The whole obsession with "serenity" is also dangerous because it's pushed way too far, beyond the ability to keep control and a clear mind . It's by and large the image the WT wants the sisters to project, that nothing ruffles them. It's superficial and artificial; sisters cannot gain a reputation for their skills and their service to the world anymore, so they compensate this by acting publicly as if they were demi-goddesses, unemotional about everything. Send the Healers to the cities as Elayne wants, and you'll soon see people start to value Aes Sedai again, and find them wondrous for the right reasons, not because they project an artifical aura of demi-godhood!

It even contributes to the overall bad reputation of Aes Sedai, whatever happens, they look like they don't care (happened even to the best, like Moiraine, Verin and co. Their lack of emotions in situations that calls for emotional responses don't make them look above the mêlée but lacking in basic human skills).

Anyway... this test originates in the Trolloc Wars, when the situation called for something like this. Sisters who couldn't pass this test were a danger outside the Tower. To themselves, but above all to the armies they were sent with. It makes sense to use this test for sisters, if you want to go through mass raisings before TG, and decide which women don't have the aptitudes or attitude to cope with combat.

As the sole universal test to determine sisterhood or rejection, it's inept. To me, it's like a test that would judge if someone can or can't be a brain surgeon, and the outcome if you fail is that thrown out of the medical field for the rest of your life...

A great deal of this is the result of the WT obsessing with the sisters "holding up its reputation", because with the WOS the AS Guild had lost the reveration of the people, and the post Breaking Tower chose the wrong path to regain it, increasing its power as an organization instead of focussing on making themselves so useful again that they'd be as valued as they once were again.

I'm kind of convinced in the AOL the Aes Sedai were far more obsessed with their own who showed selfish or inappropriate behaviour (Semirhage being just an extreme case) than they were obsessed about "standards" and "serenity", beyond the fact everyone had to pass general channelling training to gain the title (inept channellers are a danger, better do nothing with their poor skills than risk them causing harm). Nowadays, there are women calling themselves Yellows with little healing ability, because they believe the role of the AS is to heal the world... That's ridiculous... all Suana was interested in with Egwene is her strength, which equated with high standing in the hierarchy, and her strength of will. She was looking to get a new future Romanda for the Yellow, and deprive the other ajahs of that same woman. That's today's Tower.