User blog comment:Damac1214/Black Ops II - Rank Progression details revealed/@comment-4012544-20120907005156/@comment-76.125.46.127-20120907224819

Skill gap is level unlocks. A "gunner" is somebody with ingame skill. Their skill allows them to unlock more often but not better. A rookie can be aware of what is the best no matter their ingame skill. Look at the devs of GCI's justifications for sold XP boosts and you'll realize exactly how bad the connection you're making is.