Hi,
The recent incident at JFK, IMHO, demonstrates a blatant abuse of this "final authority" (based on the known details).
Sorry I don't know anything about this incident - but surely after all the effort we've invested in CRM training over the years (Airmanship in the old days) - then
all crew members should feel comfortable. If any crew member doesn't - then it means the other(s) has(have) probably missed something.
The only pressure I've ever faced is On Time Departure. If we make it - great - if not then a note on the journey log. We go when we are ready and not before.