Interesting, if brief, article. I'd like to know what's meant by "key signing parties themselves generally don't involve computers, since that would give advers

Interesting, if brief, article. I'd like to know what's meant by "key signing parties themselves generally don't involve computers, since that would give adversaries increased opportunities for subterfuge," though. Maybe I'm not cryptographically paranoid enough, but what's the harm in allowing computers on-site?