If you're a Jeff Bridges fan, Tron: Legacy was a double dose of awesomesauce. But how on earth did they turn back the clock on the Dude to get a young Clu running the show? While I wish there were a fountain of youth—or some sort of Mission Impossible-style mask?—the time-bending technique is revealed in this exclusive video.
CG-Jeff Bridges was a lot of things, but "realistic" was not one of them.
That said, I don't think it would've taken me out of the film so much if they hadn't tried to show him in the real world. A slightly fake-looking version of Jeff Bridges that existed solely in the Tron world would've made perfect sense in the context of the film, wherein he's a digital duplicate left behind.