(adsbygoogle = window.adsbygoogle || []).push({}); i only just found this, dont know if it works for xbox as i have a ps3 but.

Step 1: play in a private match with somebody
Step 2: have a friend on a different PlayStation sign in with your email and password this will sign you out.
Step 3: have your friend join whoever you are playing with.
Step 4: It will say *insert PSN ID here* has joined in the bottom left corner
Step 5: sign back in, to keep playing against your friend signed in as you you will have to both keep signing in every 30 secondsish

this way you and your mate will both be playing as the same PSN ID

kinda pointless but i thought id post it anyway

but its a private match so how is the k/d affected...