Yeah I couldn't give a shit about crit fishing, it's extremely gamey.
I hope whatever workaround they plan for Smite means that it won't be automatically blown on your next attack. It's one thing to not have any control over your reactions, it's another thing to be losing resources because of it.
Nothing worse than losing a spell slot/smite cast on an enemy that was already low HP to begin with. Or worse, on an opportunity attack against said low HP enemy, because we all know how sadistic Larian AI is.
I agree that'd be a terrible implementation. However, I believe that current Battlemaster maneuvers that only have an effect upon a successful attack don't expend the superiority die if you miss(?). Smite, if Larian doesn't add pop-up prompts, should work like this...probably.