Perrin does interrupt a torture to maim someone, but of the main cast of teenage heroes nobody else ever really gets their hands dirty. Moraine is implied to have, along with Lan, Thom, Verin, and Gawyn. Those twin Aes Sedai torture that black ajah chick IIRC, under the thumbs up of Elayne. Aviendha and all the Aiel are pretty vicious and from that last one, if I remember right, Aviendha as much as says she can't perform Questioning yet because she hasn't been taught it properly, implying that Wise Ones probably include a primer on torture, sufficient to break your average Aiel at that, in standard training. And Tuon doesn't seem to get kicks the way her mother used to but she doesn't appear to have any issues at all with executing someone on the suspicion an omen indicated future betrayal.

The authors do a bad job selling the moral boundary stuff but they do present them a fair number of times. I think they left too many get out of jail free cards on it, or diminished the character by having them react with the most irritating flavors of angst.

Though I do agree it would have been nice if some of the many conveniently deposed leaders had actually had to have been deposed with full hand-dirting by the characters.