I understood it to mean that a boy child would be doubly thrilled getting to do things that his dad does. Though I'm not sure it's as clearly true in my experience (daddy's girl/mammy's boy, and all that).
As far as I can tell there’s no biological predestination involved there though.
Sure, kids are comforted by breastfeeding (frequent food + cuddles is strong positive reinforcement) and often get attached to it and by extension to hugs with mom, but there’s no reason that fathers can’t have similar types of rewards that reinforce close bonding.
Children are quite literally addicted to mom early on. Its much more biological than simple "positive reinforcement". Nature won't leave the survival of a child to chance, or it at least tries to tilt the odds.
The poster I was responding to seemed to be making a more expansive claim but it was hard to really tell, so I was trying to figure out exactly what he meant.