I don't get it - who compared the odds anywhere in this discussion? It seems to me that the goals are just completely different. DHH is not explicitly aiming to grow the company into a billion dollar mammoth. A startup and its investors are very explicitly aiming for that (or somewhere close). Both are viable but completely different ecosystems.
You've assumed that 37Signals refusal to staff up and take speculative VC rounds means they're steering the ship away from being "a billion dollar mammoth". But 37Signals is more successful than most of the companies (yes, most) that take VC rounds, and has enviable revenue growth.
I think you're seeing a business model that doesn't fit the YC get-rich-quick mold --- and that's what it is, read the essays --- and pushing it into a "small business" bucket. The real world doesn't bucket like you want it to.
