Kirtu: Tragi-Comedy or Pure Tragedy?

I know they say that we laugh and cry about the same things, but I really have a hard time seeing the following summation of the Ugaritic story of Kirtu by Baruch Margalit as anything other than macabre:

Keret is miserable a the beginning of the story for want of a son and heir; he is equally miserable at its conclusion precisely because of his son and heir. If the curse were not so funny—Yaṣṣib examining his teeth in the cup of his hand—the ending would indeed be sad. This is the essence of the poem as tragi-comedy, mixing the tears of laughter with those of pain.

(B. Maraglit, “The Legend of Keret,” Handbook of Ugaritic Studies, 214.)

To me, the story of Kirtu is tragic, pure and simple—an old king having to fight off an heir-apparent turned usurper.