If the value comes not from the idea itself, but from the experience of having done it, your experience is just as valuable as your cofounder's. You have both d

If the value comes not from the idea itself, but from the experience of having done it, your experience is just as valuable as your cofounder's. You have both done it once at this point, and if they leave, you/the startup retain ownership of all the work so far, which is a significant advantage. I get what you're trying to sketch out, but it's a very very narrow "just so" scenario.