To many, it is insane for an athlete to do a backflip while driving a 450-pound snowmobile. But for Caleb Moore and other freestyle snowmobilers, it's just another trick. Moore performed his failed stunt during the Winter X Games on January 24, 2013 and died a week later. The stunt was difficult but apparently doable. He had done it many times before. So what do we make of this? By definition, "extreme" sports are difficult or dangerous, performed in a hazardous environment. The very essence of these sports is to push things as far as possible and then try to take them farther. Part of their massive appeal is that these sports constantly walk on the thin edge between brilliance and disaster. The fans, corporate sponsors, and especially the athletes know this. It's just a part of what they do, but the death of a 25-year-old isn't supposed to be the result of a sporting contest for our entertainment. In the 18-year history of ESPN's X Games, Moore was the first to die in competition. But why is my initial reaction, "Geez, I can't believe there have not been more." I mean, really, who thinks someone can survive attempting a backflip on a 450-pound snowmobile? But one person does it, then another and the one after that until it ultimately becomes a routine trick. And then it is time to develop the next one that will be even more insane. I am not saying that the people involved with extreme sports trying to perform some seemly impossible stunt are not concerned with the utmost in safety standards. Maybe it's because these extreme sports haven't yet reached their final frontier of possibility. However, I can't help wondering if they ever set the limit: How far should they push the envelope? So I say it's insane when I see some teenager shoot 30 feet into the air out of a halfpipe to do twists and flips on a skateboard or a snowboard, or when I see some free climber risk a fatal drop just to reach a summit. And when they have turned what I had previously considered the impossible into the probable, I ask myself: "What will they try next? And how far will they go before somebody kills himself?"