It might work for Cypher system, but it doesn't for D&D because of the whole "run out of hit points and die" concept. Since hit points are tied directly to character death, anything reducing hit points effectively becomes a cause of death. Special/cool maneuvers should be an extension of life - not a cause of death.
This would be a bad idea. It puts your "action resource" under the enemy's control. Every time the enemy hits you, your ability to act is reduced. This promotes a death spiral: When you are in a bad situation, and need to break out the big guns, you can't, because using the big guns will kill you.
Except that's also how exactly it works in the Cypher System too, which works totally fine without the aforementioned problem, and this feeds into the next point.
What is it like in general?
In the Cypher System, characters have points in three stat pools: Might, Speed, and Intellect. Your baseline for these stats are determined by your starting Type, and you typically will get these boosted through your Descriptor, a handful that you can allocate of your choice, and maybe your Focus. These points are used to fuel your special abilities or to lower the TN of a check, which include Attack, Defense, or Skill rolls. This is called Effort, and there is a cap on how much Effort you can spend based upon your level/tier.
Enemies (or the Environment) may also cause damage to these tracks, with most physical attacks typically targeting Might. When any of these three Pools get to zero, then the character becomes Impaired. When any two of these Pools get to zero, then the character becomes Debilitated. When all three of these Pools get to zero, then the character is Dead.
So how can characters manage their Pools? One of the biggest methods is through Edge. When a character spends points from their pool, they can reduce the cost if they have the relevant Edge. For example, a Tier 1 Warrior would have a Might Edge 1, Speed Edge 0, and an Intellect Edge 0. This means that when they spend Might points a Might-based ability or Effort, they can reduce the Might cost by 1 point. But they would not have an Edge for Speed and Intellect based abilities or Effort. Characters get to increase the Edge of their choice by 1 every time they advance to the next Tier. A character's type, focus, or descriptor may also confer additional bonuses to one or more of their Edges.
Also, Armor serves as damage reduction. There is no AC in the game, because the characters make Defense rolls against enemies based upon the enemy's Difficulty: e.g., a character must roll a TN 15 or higher against an enemy with a Difficulty of 5 out of 10 (DC 5 x 3 = TN 15). The enemy's difficulty also determines damage, unless state otherwise. So a Difficulty 5 monster would deal 5 damage on a hit.
Characters can also make Recovery rolls where they can recover points for their Pools, but each time they make this check, the time before they can make their next Recovery roll becomes longer.
In play practice and not white room theorycrafting, the use of cool abilities in the Cypher System has never been the cause of death. In my 5 years of experience of running the Cypher System, I have not seen a player who felt force to choose between life and fun as described or play descend into a death spiral.
