those 3 baseline are in different specs, so its basically one spell. He has a very solid and valid opinion.
Mages in frost can trigger quite a few fingers of frost, especially with the new bonuses, you can do many things on the move like tempest and insta frostfire. The potential for a dps loss is small.
Affliction can fel flame to reset the int bonus and duration of their dots and screw themselves in the process....