I'm aware of players who double box or play on two different computers on two different accounts, they'll play on their main and set their alt account to follow another player with the alt account on auto target and auto fire.
It's a shameful way to play but it may not have been an external macro. Not that it makes much difference but I thought I'd trow this in here anyhoo.
Man is a gaming animal. He must always be trying to get the better in something or other.
Warning, this poster tends to talk nonsensically when caffine levels fall below 80%.