I am using both Savagery and Primal Strike on my druid. In a heat of a battle I might sometimes click “Primal Strike” skill button even though the skill itself is on a cooldown. So whenever I misclick like that “Weapon Attack” is used.
My suggestion: since “Savagery” is a skill that used instead of “Weapon Attack” and has all the same features (procs stuff just as “Weapon Attack” does), why can’t it be used when I try to use a skill on a cooldown? I don’t need “Weapon Attack” at all, why can’t Savagery be used in all instances?
What’s the difference between what you want and “every time a skill is on cooldown and I execute that skill, trigger default weapon attack skill instead”? For instance, if Overguard is on cooldown and I execute it trigger Candence.
It’s unlikely as you said, why would someone take more than one replacer like Fire Strike and Beronath’s Fury but the possibility still exists - how would the game determine which replacer to use in this situation?