autospot - why does the client even KNOW where people are in order to spot them? Shit, no wonder the BF games are so laggy, every client knows everything about every other client that it has no need to know about!]
The client does need to know this. Game clients have known where EVERY other player is for years. Going back to DOOM! How else do you think you can change your player view while watching a demo record?
The game has to know this for many reasons. Where the bullet came from. What sounds to make and where to make them from (not to mention calculating in effects on that sound due to the environment.)