Coo' khoo... ;)
Safe to say he would only leave for something utterly amazing. The amount of job offers he's turned down is probably more than most humans apply for in a lifetime.
Back when I really paid attention to PA, I remember one of the early stories they told about Robert. In business school there was an exercise where multiple parties try to negotiate with each other while holding "nuke" cards among other actions. During the process, everyone agreed to peacefully tear up their nuke cards at Robert's instigation. After which, Robert holds up his *actual* nuke card and says "now here's what you're all going to do for me".