The smoothening virus, as per Phlox, would eventually be bred out of the Klingons. Kang, Koloth and Kor had plastic surgery to restore their ridges. From this, I could only assume that the writers might show a smooth forehead Klingon and give a character, probably a young one, a throwaway line to pay a little fan service.
I really enjoy the lengths that the writers go to connect the many decades of Trek. It just proves that they are nerds themselves, as it should be.
So, we are continuing the 'is it legitimate that an elite Red Squad exists in egalitarian Starfleet' argument? All signs point to no. Still, Nog, you go on with your bad self.