The combination of these three phases of combat makes for an incredibly deep game. Before a fight even begins, a player needs to find the right balance of breadth and depth in a particular skillset and incorporate that into his training. Specialize too much, as in the case of the early UFC stand-up fighters, and your opponent will be able to control the momentum of the match by keeping you in the clinch when you want to stand or staying upright when you want to duke it out on the ground. If you don't specialize enough, you won't be able to create a space in the game you can control well enough to make the opponent want to avoid it, and the same thing will happen.
Furthermore, each phase of combat has several different options. Randy Couture, current UFC heavyweight champion, and Wanderlei Silva, former Pride light heavyweight champion, are both known for their proficiency in the clinch. However, Couture's background is primarily in Greco-Roman wrestling, and his clinch fighting focuses on slick grappling skills to keep the opponent constantly off balance and in danger of being thrown to the ground, with a healthy dose of in-close boxing uppercuts to do some damage. Silva, on the other hand, is known for the use of devastating Muay Thai knee strikes from the clinch to demolish his opponents. Even though they're both known for fighting in the clinch, the strategies are worlds apart.
If the depth of the MMA game is hard to see in actual fights, it's impossible to see in the various UFC videogames. Fighting for a submission in an actual fight is a chess match; you need to be 100 moves ahead. In the videogame, sadly, the nuances of the ground game are reduced to button mashing at its worst and a who-can-press-two-buttons-first contest at its best. Same goes for the striking game; in a sport where mere inches can determine the effect a punch has, the subtlety gets completely lost in the unrefined, stilted UFC: Sudden Impact. Granted, a videogame is never any substitute for the real thing, whether it's Wii Sports or Madden, because it's not the real thing. But what is so profoundly disappointing to MMA fans everywhere is the game of MMA could be translated to a videogame - it just needs a game designer who understands the intricacies of the game itself. And while fans everywhere are gearing up for UFC 2007 thanks to some really impressive trailers, given the previous games' track record, it looks far more likely that we'll get a game that looks like MMA, but doesn't play like it.
Pat Miller has been doing this for way too long. Stop by his blog, Token Minorities, for more on race and videogames.