'The next big thing' may not be the default model in the valley - in fact I was impressed by the thousands of startups building tools for the guy at the 'next bench.'
Unfortunately though, the 'Next Big Thing' is pop culture, and we here in Atlanta tend to draw the game plan that I oultined from what we THINK we know about the valley. Even when what we're pursuing isn't a 'next big thing' opportunity, and even when nobody here would ever fund such a thing - we have the reality on the ground in CA in our minds, and look forward to raising money instead of getting our first check from a customer. Our ideas are larger than our budget. Its there in most everyone, at a deep, deep level because the stories of the icons we look up to enforce it.
Therefore I would submit that my advice is good, because I've seen the pattern play itself out here a hundred times. We need customer driven development in Atlanta. Those are the kinds of opportunities we can pursue and do well at. But I don't presume to give advice to SV startups - I don't know anything about those. Obviously someone like you can pursue any idea he wants and make that work - you and your companies have a thousandfold more resources than we have available to us by virtue of your experience and location, and you have first-rate talent for building and picking startups.
The 'right model for the right kind of startup' is right - but most people mess that up terribly, so the advice is insufficient. My suggestion is that Customer Driven Development be the default that we hold in our heads - rather than the California State of Mind, which is ruinous to us.
Bad advice is espousing and embracing the Valley model (as we understand it) to the rest of us, because it does not apply. How many of your companies raise series A's right out of Y-Combinator? Do you have any idea how unlikely that sort of thing is here? A Y-Combinator startup has options other than customer-funding once they reach the stage of exiting Y-Combinator. An Atlanta startup usually does not, unless they leave. The sooner we accept that reality and deal with it, the sooner our rate of growth will increase.