Does divorce occur and a curse befall one who says, "I'll be the son of a dog if I do such-and-such, by triple divorce," and then does it? And does this phrasing fall outside the scholarly disagreement regarding the oath of divorce?

If someone swears "Talaq (definition) upon me" (meaning, "Divorce upon me" or "I am divorced"), intending only to prevent himself from doing something, then if he does that thing, he has broken his oath. The majority of scholars hold the view that he is bound by the triple divorce when he breaks his oath.