People self -sellect themsleves into particular groups. If your objective is to go around the world, then trans-USA is a smaller objective, and when you are out there you will rub shoulders with others from granny and grandpa to 8 year olds.
We have the occasional thread here that goes "well I am almost ready to leave. In a month I will cycle from Seattle to LA, and I was just wondering what I should do to approach potential sponsors who might want to give me money and gear. By the way I have a website and am raising money for Doctors Without Pensions, if you feel you can give something go to...". The response is normally a collective sigh of "give me a break". Sure such a trip would be beyond the powers or interest of the vast majority, but it doesn't really merit a line in the local paper either. That is why we have crazyguyonabike.com.
I think we can all sort out the difference between a personal preference, like short tours; a personal best; and a world class acheivement or first. Thomas Stevens Cycled around the world over 100 years ago, the conditions were harder, the gear hoplessly primative. Not a whole lot worth making your life miserable for has entered the record books since.
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