In addition, most bosses fight melee at least in part. i honestly dont use slow myself. i rely on my high defense to save me. Kiting is a way of life for all classes in pve. As a tank I enter a mob, pull, slam, then sheild and use the aoe knockback skill(forgot the name) rinse and repeat. With most bosses I use my taunt skill which is NOT an aoe, then stomp, shield, taunt, and again the aoe knockback skill. Since there is only room for 8 skills on your map I leave off slow. It would be useful in a boss fight or against high hp minibosses, but not much else.