The Mobility Course in the Modern Warfare 4 beta is a proper test of nerve. It sits inside the Proving Grounds and throws movement, shooting, and quick decisions at you all at once. If you are chasing the Clockwork Weapon Charm, the Expert route deserves more than a quick attempt, and a look at MW4 Bot Lobbies may help you warm up before taking on the timed run. The required result is an S-Tier...