Great actors can make you forget that you're looking at them instead of the character they're playing. Tom Cruise has never been able to do that. It reminds me of a routine I saw a comic do on the Tonight Show once: "In one movie Tom's a pilot. He's a pretty good pilot, until he loses his self-confidence and gets it back with the help of a beautiful woman...in another, he's a bartender. He's a pretty good bartender, until he loses his self-confidence and gets it back with the help of a beautiful woman. In another, he was a race car driver..."
Oh, sarcasm!
On a serious note, you reminded me what it was that made that movie so great -- Dustin Hoffman. He was outstanding.
Don't forget, in practically every Tom Cruise movie, there will be a scene where he sprints--maybe a block, maybe a mile, but he's gonna sprint. Must be proud of his running ability.