Heartless as it sounds, it is absolutely fair to think about how to protect the business and yourself in the event that a fully vested founder were to be unable to do the duties one has reasonably assumed they would do.

Ownership shares are not like salary (imho): they're not just for past work, but also for future contributions.

Without specifics on to what extent exactly they were planning to dilute him, I am not prepared to condemn BillG. YMMV.

Jobs' actual cheating through a straightforward lie to Woz wrt how much they got paid for Atari's contract job they did is FAR worse than a planning conversation BillG had. IMHO. http://www.rotten.com/library/bio/hackers/steve-wozniak/