Fair point, though the ages of the actors in MOS were all over the place too. IIRC, jonathan Kent was supposed to be in his 40s but was played by a nearly-60 Kevin Costner, while Amy Adams is 6 years older than Henry Cavill and 9 years younger than Diane Lane. So the age disparity wouldn't mean an awful lot (don't forget that women often play older in Hollywood - in Blow, Rachel Griffiths played the mother of Johnnny Depp, who is older than her.