No unforseen side effects and hideous deaths. No flu-mutated airborne plague of death wiping out billions. The augments stay alive and stable (well, as stable as the human augments were, though it could be argued they were somewhat mentally unstable). Do you think it would result in all out, total war between Earth and the KE? Or... would it result in the Klingon augments attempting to take over the empire and enslave / wipe out the ordinary Klingons? Would they end up having their own eugenics war? Discuss.
Since a bad hangnail is reason enough to send the Empire into civil war, I imagine the same thing happens here.
I think that the augments would try and take over and either enslave or destroy the regular Klingons. Klingons so highly value prowess in battle that the augments wouldn't see the weaker, regular Klingons as "worthy."
If you assume that it worked perfectly, which seems highly unlikely as the Klingons used human DNA to start with so what actually happened to the Klingons makes more sense, they would have behaved like human Augments and thus attacked everybody. I fail to see why it should remain an internal matter and merely lead to civil war. That was actually the point of the Augment stories, to show that in an age of space flight Augments would attack everybody and thus cause serious concern among other species.