youtube video, learn spawns, memorize the steps and patterns, practice until perfect execution. you ONLY need to make it to the hostage room in time. after that, your timer is reset so you can take the shot(one chance to get it right) and jump out. it seems hard to do, but it just takes practice. MHC wasn't near as bad as WaW on veteran, AKA call of 360* constant raining grenade spam between MG nest chokepoints.