csroy:
For my part I see the uncertainty as part of the game. In an open system you know how good you are, you know how much more you can take before you drop out of a fight and how much more resources you can expend.
I urge you to examine this statement more closely.
Imagine you, as a person, trying to leap over a gap. You, as a person, have a sense of your own athletic abilities. You know how fast you can run, how far you can jump, how confident you are in your stride. Your brain naturally takes all of that self-knowledge into account when eyeing a gap, and gives you a good "gut check" of whether you can feel confident in jumping that gap.
A character's statistics, in a game, provide the same function. They give a player a
feel for him- or herself, and let him do the eyeing and estimation. They tell the player how fast the character runs, how far they can jump, and how confident they should feel in their athletic abilities.
Furthermore, a person getting pummeled about the head and face has a pretty good idea if he's winning or losing a fight, and can
feel the effects of fatigue, injury, and blood loss. Functions like health levels, conditions, and hit points provide that same feedback to the player. They know the difference between taking 3 HP and 30 HP, and how it relates to their character's feeling.
Without that feedback, without that degree of self-knowledge, a black box game can induce a feeling of extraordinary blindness and uncertainty, and not necessarily the good, horror/mystery inducing kind.
You can't assess a situation without a baseline. You can't determine if something is a risk without knowing what constitutes a risk. Making a decision based on virtually zero information - about your character, about the environment, or about the thematic or narrative underpinnings of the story you're trying to tell - can be a truly infuriating experience.