if you have GilesTrinity Plugin
there is a default setting so that in a 40 Radius range, the bot will only Fight groups of 2+ mobs.
so it will totally sometimes skip a Mob every 20 to 30 secounds.
This setting is super great in inferno.
the only downside I can see is that when the bot is full of items, it will try to port to town over n over again while a mob is attacking you, hope-fully you have a good dps merc.
if your Botting/Power lvl'ing someone.. you will want to reduce that number to 1....
Full white Mob clear.