Nah. They think 6 squares is a reasonable distance to move in a board game. If players were moving 3 squares per turn you couldn't cover much terrain. Note that 4th ed simply uses the term squares. I'm not sure if they ever state that a square is 5' or if that's a holdover from 3rd ed. I prefer to think of a square as a yard. That gives you a more realistic move speed.
That's an argument for another thread. I don't think that WotC believes real attacks work like they do in D&D. AC is a simplification. A more realistic system would include facing rules that could account for which side of your body is more well guarded. IMO, that's too many rules and I wouldn't want to play that game.I think it is patently ridiculous that you can be attacked on your shield side at all. Shields block incoming attacks, not simply make them harder to get through. They should also have included rules for helmets to reduce crits or something. How can WotC really think that a lethal blow can happen if you have more armor?!?