Single boxing is way harder. You have to wait for everyone else, and 80% of the time they're inept morons, not to mention how differently you have to play. You have to watch aggro and deal with others being stupid, and then you have to worry about how loot gets handed out. And that's on top of fiddling with abilites you never use. What do you mean, sap this, trap that? Can't we just kill it?