The change to frost shock is simple.
Frost shocks diminishing returns kicked in just as fast as cyclone, meaning a slowing affect, not a complete lock up, diminshed faster then hell.
Frost shocks also put your shocks on cooldown and while the change doesn't affect that it makes frost shock alot more appealing. Plus frost shock lasts as long as it's cooldown if I'm not forgetting my class already so now we can catch you running sons of well you know whats.