Maybe he just has amazing aim rather than auto aim. That can only be used in single player anyhow, so either way your friend would be stretching the truth a bit.
I'm fairly certain that there is NO auto-aim for online play. But I can tell you one thing... even after playing SOCOM 1 back in the day, it's the first thing that I turned off when I started the single-player game when I initially purchased SOCOM 2...
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