I agree. I think doing Extra for personal development is rarely aligned with job performance, and you have to be very, very good and conscientious about creating that alignment. More often people get away with it by tanking the productivity of their coworkers and making the business increasingly reliant on their personal productivity. But to do this you need weak or absent technical management.

I think doing Extra, More, or "Nothing" are all fine choices, if by "Nothing" you include spending time on family, community, health, and non-professional education. For professional advancement, I think "More" is a fine choice if you have good management. Management should have the perspective to appreciate you making the right choice for the business. If they don't, well, in that situation, I find that advancement depends on selling yourself to people who only care if you're delivering good news for them and can't appreciate anything else.