On the rare occasions when fighters have dared to publicly ponder the notion of holding titles in two weight classes at once, really tends to be sobering.
Conor McGregor, of course, recently tried to go for double gold, only to lead to a chain of events with Nate Diaz no one could have foreseen. Seven years ago, then-UFC lightweight champion B.J. Penn lost a one-sided fight against welterweight champ Georges St-Pierre. And once upon a time, an 8-0 Brandon Vera proclaimed he was going to hold the UFC heavyweight and light heavyweight belts; he's 6-7 since.