I think a more feasable idea would be to write software for the PC that, when ran, joins a system link game and drops a few bots that way. In a way, it's like the PC is the player.... I'm not sure if this makes sense; if it doesn't, look at EraserBot for Quake2. If I'm correct, that's how that particular modder pulled it off, and presents a better example than I can describe.