Winning due to tactical skills (Heres the plan. You go left I go right we shoot our nades get them shooting us then Bob you come in with the chopper clear the way for us etc etc) while the other team is confused and taken by surprise.
I like killing people by tricking them and not just having better skill, this guy who was clearly better than me lost to me because I do things like go around a corner, crouch, and get a quick headshot when he turns expecting me to be down the hall.