Wind dynamics? Wind has nothing to do with sway. And as far as the G3 being better, it most certainly isn't. The scope, sway or no sway, is better and more efficient for picking crosses and just long range shots in general. Now with the G3 it obviously has some close range capabilities but and M4, Ak, Mp5 or any other automatic gun will easily out do it.
Oh and the whole "better players" not needing to scope thing, try saying that to any Cal-M/Cal-I team and they'll more than likely have the same thing to say as I did. See that every good Cal team has a scope designated scope for basically all the maps.