Burning Soul and Frost Channeling.Follow

Can anyone tell me if the reduced threat from Frost Channeling will apply to Frostfire Bolt in the same way that the reduced threat from Burning Soul does. I want/need to know 'cause ive been told that Naxxramas contains AoE fights and i was hoping to put one point into Imp Blizzard and then put any left over ones into shatter. If anyone has tried this coiuld you tell me if it screws your dps or not?

Thanks :)