Well, first, he will never outwork Fedor at this age. It won't happen. I can see Couture winning by elbows because of Fedors little experience against them. Or, of course, by a cut.
I'm going to put the chances of this card pulling together like this at 1000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 to 1.
add a severn-gracie and shamrock-kimo and that would be a really nice card. but seriously, i don't think it could happen. it's like mayweather-delahoya and cotto-trinidad in a boxing card. a fedor-couture fight will sell so will a rampage-chuck fight. so why put both in a card when you can twice as much money. and it doesn't help that ufc72 is fresh in my mind. if you can get those guys to fight each other, do it sparingly. don't let another card like 72 happen again
Keep in mind I pick fights from a gambling / value standpoint. I think Randy and Faber would be big enough underdogs to get a high enough expected return for me to take the bet, thats how I pick fights.