I went through Techstars in 2010 as their first solo founder, and I failed pretty hard. The combination of talks, mentor sessions, wooing potential team members, and pitch practice left me almost no time to code and plan the product. For the final pitch, all I had was demo ware, and I felt an idiot getting up on stage.

It was a worthwhile failure for me, I made some great friends and learned a lot, but I'd counsel any lone founder to focus on growing some kind of support team around them as the first priority. I would never contemplate an accelerator as a solo founder, but I have nothing but admiration for those who have managed it.