Hi,
I just noticed while testing the new frost mastery that if you icelance into a RoF'd target, you don't release icicles. It does not work all the time, but it was like 80% of all tries.
It's pretty minor and I don't really play frost (I like arcane more) but maybe some experienced frost mages out there can do something with this information, even though RoF has a 45 sec CD.
I hope this will help someone dealing with the new mastery.
Edit: Works better WITHOUT FoF Proc, but its still possible with it.