Not to say that a game like that wouldn't have some novelty value, but it would be really boring. Not to mention prohibitively difficult. Also, if you wanted it to be truly realistic, you would have to take into account that piercing is not the only way to do damage through armor, you can just use a massive war hammer where the energy translates through the armor and deals some pretty serious internal injuries. In fact, you would almost certainly need to do some information gathering in the real world if you wanted it to be truly realistic.
For example, i had always thought that a sword or axe would go through chain-mail with a direct hit, but on that show where they compare ancient soldiers against each other, they had some "samurai" try to cut through some chain-mail and they couldn't. they didn't even come close. On the other hand, something like a very long hilted curved chopping sword would probably cut through to some extent. Don't know what it's called, the guy at the renaissance fair called it a "Mongolian long sword" but googling that gives a completely different image. Even then, a system like that almost completely reduces the game to nothing more than who has the best gear. Particularly since a truly accurate game wouldn't have "health" it would need to be something like a kill or not system, or perhaps health based on bleeding.