This is quite obvious. So maybe the solution would be to make Fel Flame actually worthwhile and not being able to cast on the move like an idiot.
To me KJC is actually the reason why i dislike playing my lock. Its just way too easy not having to think about when and how to move, in a game thats pretty much based on movement. Yet i still have to take it, since its required to perform optimally. This ontop of having an already dumbed down Rotation as Affliction compared to earlier days, makes it really not fun to play. To me the Demonology Model seems perferct. Being able to DPS on the move (in Meta), but having to plan ahead for it to actually work well.
Similiar things could be done for Affliction, if Fel Flame wasnt so shit...
EDIT: Btw there already is a somewhat fun mechanic in place for movement fights, its called pandemic. Sadly it suffers the same problems as Fel Flame, as it fucks up the snapshotting of your dots...