Are there misconceptions with what a CTO actually entails? I've not heard of a CTO that does any physical programming with respect to their job. This might be different in a small startup but my understanding of a CTO's role is to guide architectural and development goals of the company as a whole - and to hire great people to implement that vision. It sucks he would have to leave but part of me wonders why he thought the CTO role involved a fair amount of programming and why he wouldn't just move into a lead developer role as opposed to leaving entirely?