I got some yellow bar and briefly some red bar lag the other day. It didn't help me one bit. I'd die before I saw the guy shooting me, I'd get killed through walls and I wasn't getting score credit for kills/assists. On the flip side, I did manage to finish my postmortem bounty fairy easily. Since if I did kill someone, it almost always meant I was already dead, since they killed me a second or two earlier. That must have been a surprise for them.