Reading through your list of points, it sounds like you're trying to justify not just trying and seeing what's possible. There's no golden rule or answer to starting a business, but there are plenty of successful businesses that started as a small part-time endeavours.
As a start, 37signals did it with only 10 hours a week:
> Reading through your list of points, it sounds like you're trying to justify not just trying
Correct. "Trying" is risky, I'm just attempting to measure how much more of a risk it is to do it on my terms. Prior to today, my plan seemed guaranteed to fail no matter how strong the idea, and I would be unhappy in that situation.
Thanks to the comments here so far, I feel now like I'm not guaranteed a loss under my low-hours restriction, and the risk of failure is acceptable given my desire to see my idea to fruition, and my expectation for its potential.
Your link was brilliant, motivating and exactly what I wanted to hear. I'm surprised I hadn't found that before.
As a start, 37signals did it with only 10 hours a week:
http://www.37signals.com/svn/posts/1078-it-doesnt-have-to-be...