From the tone of his blog post yesterday, I was prepared to see Internet entrepreneur Mark Cuban fall down on the dance floor, writhing in pain as his career on ABC's "Dancing with the Stars" went up in flame. Instead, the Web's ultimate good-time Charlie kept jazz-handing his way through the number, smiling all the while. Was he hopped up on hardcore pain medication endorphins or what? Still, a lesson for every startup founder: Set expectations low, and then exceed them.