I think it's a timing thing. From the boards point of view, there is value for Tk to take leave and value for Uber to have someone else at the helm.

Although from TK's point of view it would really suck. It's like loosing your mother and a child.

I read somewhere that the best thing to do to cope with extreme personal tragedies is to keep oneself busy... what's better way to keep oneself busy than to work.