Derren said:If the game has dragons in it its completely normal that balls are cubes, adventurers don't have to train to learn every possible trade on earth, people regenerate by their own power and swords can only be swung in a certain way once a day, because as soon as the game has one thing in it which is not completely realistic it can be as silly as it wants without it making a difference....
Balls aren't cubes. They might be approximated as cubes to make life easier on the players, but that doesn't mean the characters see cubes. Same with hitpoints; good approximations for the players, but not real from the characters' points of view. Same with the grid map, or the way that so many things mysteriously happen in increments of 5% probability, or the way that 4:59 of rest isn't too helpful, but one more second makes a huge difference.
As for learning every trade... There aren't craft or profession skills, so there isn't really any reason to believe that the PCs get better at that. After a lifetime of fighting monsters (and/or getting closer to being a demigod), they do end up stealthier, more perceptive, more athletic, and just generally worldlier than a farmer who spends his life farming. But mostly, they are heroic entities in a world where that actually means something more than just strength of character, and so they get all kinds of little benefits from being heroic.
Basically, 4th edition is good at generating a cool game play experience for the people playing it, and good at generating events that, in retrospect, can be explained quite reasonably within the context of a heroic action story. But it doesn't stand up too well if you try to push at the game's internal physics. It's just not designed for that.