I've been thinking about difficulty settings and mechanical design a lot recently (mostly in terms of RPG's) and one thing that always seemed a little odd to me was "critical hits" in games. I found it especially interesting when this random mechanic was implemented but with the ability to increase its power or chance of occurring. I especially found it interesting that sometimes its likelihood can be changed by the player, but the information for doing so is hidden (such as increasing party members chance of critical hits depending on a hidden "friendship stat" between the characters). So I was wondering what people thought of critical hits in games. Do you find it takes away from the feeling of control or skill of the player; or do you think it adds to the game by giving an extra hope for success in an otherwise unfairly balanced match-up (such making you continue to play when you have very little health left and the enemy has a lot since if you get a critical hit, you could still win)?
Also, if a term is in " " 's then its a term that certainly isn't official but I can't think of a better term (and hopefully if you don't know it, a quick google search will give some examples).