The wording on lightning shield's shocking aspect has been changed from landing a spell to landing an attack for a trigger. With things like aoe and chain lightning will you be getting multiple procs per spell or does the wording just mean that attacking with your weapon etc counts too?
http://us.battle.net/d3/en/calculator/wizard#Ul!!aa <that could a possible combo for mass proc since it has no notable cooldown.
But its current wording seems to suggest that it is not limited to once per cast.
One thing to consider is that you are losing the Defensive Shock from the base skill.
So, its not likely to be as OP as you might think.
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