I very rarely find throwing a potion is the best choice for my party, or the enemy.
The ennemy only has healing potion so yes, it may not often be the best choice. In fact in my playthrough it is often a bad choice for them as they are usually healing both his ally and my character(s).
But you, as the player can use it with all kind of potions so it definitely is a very powerfull choice.
Full party invisible, full party giant hill strength, full party resistance, full party haste. Cheaper than 4 level 3 spellslots!
Not using it myself as I find the mechanic both ridiculous and overpowered... but that's definitely another cheesy/overpowered/optimized option that allow players to bypass the challenge and some of the core mechanics set up by the devs. Which looks very wierd to me in a turn-based combat system.
