My father was 50 when he sired me and 54 when he sired my sister. My sister is a scientist at LANL. She is currently in charge of the world's most powerful microscope. I was 35 when I sired my daughter, she is a highest honor student college senior finishing a double BS degree in math and chemistry. As to me, I am the black sheep of the family, being only a college dean. Granted this is anecdotal evidence instead of 'science' but I still smell a rat.
I would bet money that this research will be contradicted by further research which allows for more factors. The most successful sperm must out compete millions.
Seems on the level of nutrition 'facts'. Butter bad, margarine good.... no margarine bad butter good, eggs bad. No eggs good, milk bad...no milk good, bacon bad....no bacon good and so on. The same apples to pharmaceuticals but usually in the opposite direction.
The usual sloppy statistics improperly considering all factors reported by the scum of all professions, the one without even the slightest pretense of an ethical code -- journalists.
Read not to contradict and confute, not to believe and take for granted, not to find talk and discourse, but to weigh and consider. - Francis Bacon