You won't have to worry. I would never get to that point. It's a last-case scenario situation. Istredd isn't like Yennefer who has always danced on the edge of too much. Who craved power, drank in the power. Now she has learned control and when she regains her magic, she will be all the stronger for it. But to get to that point, Istredd would have to completely lose his mind.

But who knows what is possible, if the right buttons are pressed.

No, our rector or rectoress turn them into eels. I don't know if they feel pain or even know what's happening. From what Yennefer told him, probably not. It didn't sound like a struggle. He knows what their teachers are capable of. They could make anyone black out, in the kindest way possible, before turning them into magic batteries.

It would be wasted power to let them leave. That's the way they think.