Yeah, don't do it. Leave a bike length between you and the next bike. If you can't hang here, find a slower group of friends with whom you can hang there. Injury is the absolute worst thing. It takes absolute concentration, good reflexes, and most importantly, the right reflexes to ride fast with a small gap.

I've never had a paceline injury, and no one I ride with has ever had more than a little scrape out of one, and very few of those. But these are all very experienced folks who've been riding together for many years and have nothing to prove.