The Minion Damage is simply increased global damage. It does not apply to multiple types, and thus does not apply twice to converted or added damage from passives or items such as Lua error: Error: invalid field alias "items._pageName"; aliases cannot contain dots or quotes...
New copies of this item no longer have a chance to trigger Lua error: Error: invalid field alias "skill._pageName"; aliases cannot contain dots or quotes.. on kill. Now causes increases and reductions to Minion Damage to also affect you at 150% of their value (from 100%), which affects all versions of the item. Existing versions of this item now trigger level 10 Summon Spectral Wolf on kill (from 18), however the skill has been significantly changed, and you are now granted added physical damage to attacks. The minions from this skill are now also affected by your modifiers to critical strike chance and critical strike multiplier. In other words, it's a lot better now.