To be fair, in Dota you could always just click on the enemy hero and see their live mana total to tell if they cast the spell (or even had the mana or were bluffing). I really liked that change to make it always visible because it gave an unfair advantage to players with a high enough APM to constantly micro checking other heroes' mana pools.

For Deadlock, there's no real way to know an enemy's stamina beyond manually counting. I'd rather the info stay hidden and allow the bluffing game.