[morsch]

It's my sense that a more prosocial policy wouldn't put two stressed parents ..., and then know that them taking 8 months is the reason the other parent could take only 6 months.

People usually figure this out months in advance. Nobody I've talked to seemed to find divying parental leave particularly stressful. Maybe your experiences are different.

I still don't see what alternative you're proposing regarding parental leave other than having a fixed allocation.

I'd be open to less flexibility, mostly because it'd get more dads to take more than the current "minimum" of two months (leaving twelve months to the mom). I don't think that's a very popular (and politically viable) position, though.