76 hours at 12-year pay with 10% profit sharing grosses one about $50k/year more as 73NA over 777B. The ones I see willing to make that jump, give up seniority and work significantly harder for $50k/yr (all or much of which could be eclipsed with some GS action as 777B) are those who are tired of being or becoming brain-dead and/or have recently become empty nesters.

Yes, I'm stereotyping here based purely on what former 777Bs share with me. I do not have this choice to make myself and obviously can't speak for the masses.