I think that this Dukat would tell you, if he were not under the vow of silence, that to make a point and convince your opponent is worth something, and I think he always liked the thrill, in debates, when he was able to deliver superior logic and his adversary would concede. That part of them, I think, is the same, and I think it's what drew AU Dukat to the idea of being a state prosecutor (called prosecuting nestor, in his world)--he'd get to deliver a verbal smackdown in a venue where it's appropriate.
What's different is that this one would be disappointed at a loss, possibly still think in some cases that his opponent is being obstinate and refusing to see the evidence, but breaking a person...that's something that he finds repulsive. And I think a lot of that has to do with how he was raised, and the faith that he holds...it's given him a guiding star and a reality check outside of himself that the canon Dukat didn't have.
I figured as an alien, he might not understand what goes on with horse training (and other species that use prey animals as their mounts), or may have only seen the most flagrant examples. The relationship between a Cardassian and a riding hound is, when you get down to it, a predator-predator relationship rather than a predator-prey one, and that's fundamentally different in the way that the two creatures relate to each other. That's why he looks at the process on other worlds--Earth would be included--and sees only terrorizing an animal (even though like I said, I know that when done RIGHT, training a horse is about establishing trust and confidence in the animal rather than breaking its spirit)...and in his alien perspective, he doesn't think that's right.