You must understand, Ariste, that while we do attempt to influence genetic evolution, we only do it to achieve true and lasting human supremacy. Anything less is an existential risk to our very existence. We face inevitable genetic de-evolution if we do not separate true humans from animals.
That is why our faufreluches are so important. Our feudal system's emphasis on pure bloodlines and ancient genealogy allows our breeding program and arranged marriages to produce heirs fit to rule us in the challenging times ahead.
And before you protest, yes, that does include your ill-fated betrothal to Feyd Rautha. As difficult as it was for you to countenance, your matching was based on careful genealogical research and political considerations. Love or revulsion, for that matter, has little relevance to the matter.