If youre on haste then dont cast skills such as longshot or sharpshot and expecialy no double shotWhen I'm killing bosses. I usually bolas double the sharp shot while using haste elixer. Then repeat once bolas is ready again. Works very well for keeping aggro. Except when you don't want it so you can heal. It's kinda hard to get rid if it :p
Bolas and auto, thats what the haste is for, super fast auto!
His goal is agro not best dps, skills draw much more agro then autos.