"I have minutes/hours of experience more than you have !" aside maybe for video games, would you really take the advice of someone based just on that ? :p
When it comes to twins, the whole older/younger feels pretty much irrelevant to me. If they want to use it, somewhat, sure, have fun with it, but wouldn't take it into account for things like studies. Unless one got held back a year, they have pretty much the same "exposure" to school and studies, it's really a matter to how good they are at studying, which is unrelated to being older or younger in their case.