Don't get me wrong, I think this is a great match-up, no doubt about it. But why would you put essentially the two best contenders against each other when you've got much more beatable guys in the division for each respective contender, when it comes to a one-fight track to a title-shot? Everybody has been clamoring for a Jones/Gustoffson rematch, yet yall want him to fight Daniel Cormier? That most likely THE toughest match-up for Gus. I'd rather Gustoffson fight lil Nog, and Daniel fight Davis or Thiago Silva so you could most likely have two contenders already lined up for the champion.
Having DC and Gus fight each other knocks off one of the best contenders and the loser would probaly have to get about 3 wins in order to earn a title-shot or sell a rematch, which IS NOT a foregone conclusion, even with how thin the division is. You could have an injury during camp, and injury during the fight, a decision not go their way, or they could just plain get knocked off.
So while Daniel Cormier vs Alex Gustoffson is a great fight to make for the here and now, it's probably not the smartest fight to make for the future of the division, atleast in my eyes.