Here's the trouble with the Up Goer Five craze, in way more than 140 characters. Yes, it's funny to see how difficult it is to explain something even somewhat complex using only the most common thousand words (or ten hundred, since "thousand" doesn't make the cut). But it seems that a lot of scientists who are sincerely interested in communicating to non-scientists have become convinced that Up Goer Five Text Editor offers useful training in writing simply about complex topics. This seems to me to be completely bonkers. Of course, I can't say "bonkers" in the Up Goer universe, because it doesn't make the cut. But you know what I mean. And my children know what I mean. Why? Because an average six-year-old has a vocabulary, by some estimates, of 16,000 words. And an average adult's vocabulary is around 60,000. So Up Goer Five is only useful if you are going to talk to pre-schoolers. For an audience that's any older--even second grade--I can't see how it can help. And the time people spend using Up Goer Five is time they can't spending developing their skill with metaphors and the other tools of language that make it possible to convey the gist of complicated ideas. I even get the feeling from some commenters that they see their failure to describe physics or genetics with Up Goer Five as a validation of their feeling that it's hopeless to even try. And that's the worst effect any writing exercise could ever have.