Good points, but the most damage has been made by him faking the development process: telling your cofounders that you're moving along, while secretly preparing

Good points, but the most damage has been made by him faking the development process: telling your cofounders that you're moving along, while secretly preparing to launch a competitor isn't what I call "branching" in my book. You're right, I may come across as strongly opinionated on this matter, as someone who worked his ass off only to learn some day that our partner has had prepared a brand new corporate entity where he's been pumping our IP for stock, leaving us with stock of an empty "shell". Lawyers helped, sure, most of what we got back went straight to their own pockets. Having two guys work for $400/hour isn't going to help you much. So... I wouldn't call it branching when you're essentially paying (with your time and effort) for someone else's product launch. If I remember the story correctly, Zuk launched Facebook within weeks (!) after finally admitting to them that they're screwed.