We have known since launch and they apparently don't care because it's a "feature" in their game.
BTW, the backstab abuse doesn't work because A.I. has close range area detection. So only for ranged attacks ( Such as over 9000 eldritch blasts, spells, any kind of projectile and throwables ). I haven't tested other gimmicky crap like casting darkness/clouds and hiding just a feet from the enemy though but you could test it yourself. I mean there's an insane amount of sillyness anyway.
One of the exploits against Bulette is that you drop darkness by him as you do a stealth attack and he just stays there dumb doing nothing, because the AI is that bad.
Sin Tee uses the spore cloud for a fog, it gives him haste on top, and he basically kills Bulette in 2 turns while hasted and Bulette does nothing while he sits at its flank hitting it with dual wield flaming axe.
Stealth and consumables are straight up breaking the game. Oil of Sharpness, Invis pot, Potion of Hill Giant Strength and Spore Cloud is just busted. Dipping weapons in torches you drop is basically almost like a 30%+ damage boost at no cost other than the slight inconvenience of dropping down and picking up torches in between attacks.
