This conclusion applies only if you're thinking in terms of dmg. As long as you include CC into the equation, the ability appears to be balanced once again.
A usual player is expected to think also a bit tactically, treating abilities like e.g. cards in card games. If they know that their ability A counters opponent's ability B that is off-CD, it's worth to keep A "in hand" for a while (i.e. as long as its virtual potential is of a higher value that its applied potential).