I always keep reminding myself to never get overconfident and think that I can handle anything that comes along, but at the same time I've allowed myself to go into situations where I expect there is a good chance to get dumped. Even so, I've either been lucky, or my limits are set at very prudent parameters.
Carl, you made a very profound assessment when you stated that people often don't know what they don't know. My belief is that there is only one way to overcome that and that is experience, experience, experience. But one must survive to gain that experience. You have to push the parameters cautiously, but never venture far from your comfort zone. It is a slow process.
In my case, I've been fortunate to find a couple of boats that are so much better than I will ever be and that makes the process easy and fun.