— opening example: dedicated parenting hours
Some fathers of primary school kids “sink” virtually all their free time on the kid. They presumably reliaze the strategic ROTI.

However, the proven reliability of this ROTI is highly questionable.

If their kids turn out to be “successful” by the conventional (academic, brank or financial) yardsticks, then it may have less to do with these dedicated hours.

Leverage … is reduced by the large tcost (energy sink)

— Yoga classes …. Tcost is rather high. I can’t spend 3H/day, even considering the strategic ROTI
— piano practice?
— coding drill … If you don’t practice speed coding, or you do that without fully digesting the problems, then even 10 problems/week over 3Y (150 weeks) won’t be enough. You will hit dimishing return.