I guess it comes down to what "it" is. My sense (and this is just a personal orientation) is that if a CEO came to me and said, "Hey, I need a CTO for this new business I'm building", the very _next_ thing they say is really important.

If it is a) "Right, I've had this braingasm, and you need to build it, and for the privilege, you get 5% of the company!" versus b) "Right, I've had this idea, done some market validation, lined up our first 3 customers, and now we need to do some technical feasibility and put a team together to build this, and as CTO, I need a 50/50 founder, what do you say?" then I will pick b) over a) every time.

To be fair, those scenarios are cartoons on purpose, but I just wanted to make the point by highlighting the extreme cases.

As far as "sell before you build" goes, I think that really does depend on the problem you're solving. If it's a tech-powered business model innovation (where the tech is a commodity), then we are in 100% agreement. If the tech is a bit trickier and you need to show something special before funding (let alone clients), then I take a slightly different tack.

I'm not sure I get the last point about wide eyes, but I suspect it's immaterial to the bigger point.