Can playing on a heavy firefight on campaign improve my Xbox LIVE skills?

I think in general playing will help you, but don't worry so much about the numbers, just have a good time (I know, it's tough going 1-11). I am in the same position as you. I have about a 0.90 K/D, 1 prestige rank 64, about 7+ days of play time. I'm on 1.5MB connection with usually >125ms ping. I generally have a hard time getting more than a 5 killstreak.

At first I liked Ground War because there were so many more targets, then started playing the objective mosh pit types when the map packs came out (which are now gone) and loved playing with fewer people. I play with a group that likes Ground War for the Party Chat. I hated it again because I was always getting blindsided, but I've gotten the hang of it again.

You may be either too campy or too aggressive. Are you getting shots off and you die first, or are you getting killde from people you never see. Try no to be out in the open much, try to find cover more, but don't stay in the same place too long. You may also just have trouble seeing people, like a mat

Halo: attain, Portal 2 (an unique co-op marketing campaign), Borderlands, the drawing close Borderlands 2, the drawing close Mass result 3 (not the foremost marketing campaign, in spite of the undeniable fact that it could have its very own tale element), The Lord of the jewelry: conflict in the North, delusion III, Left 4 ineffective, Left 4 ineffective 2