Dave & Dave, I get where you're both coming from, but as an engineer, I tend to think twice or more about a problem, then get it on with it. If I have a pretty good notion of where I want to end up, it makes getting there a whole lot easier. Since I've never built an airplane before, I'd rather play a few mind games first so that I'm not having to say (too often) "Sh*t, I just cut that piece of tubing too short!"
Bill