Does changing the odds from 1 in 1000 to 1 in 100 really alter your game? Really? I guess, if every session each player is rolling the dice a hundred or more times - or anywhere near a hundred times - it does. If you sit down and tell someone that they have a 1 in 100 chance of survival their reaction will not be significantly different than if you tell them it is 1 in 1000. They are both horrible odds to have stacked against you, and if you have any imput to the situation, you had best look for a way to increase those odds.
But, I think that this idea is just another symptom of the epidemic of idolotry in the gaming industry I call the worshipping of the Gods of Chance, the Dice-Lords if you will. That everything must (EVERYTHING! MUST!) have a random chance of going wonky.
Personally, I believe the best games are a balance between the two extremes: 1) the random roll-fest, and 2) reading a novel. I do like the bit of randomness the dice can interject into a game, the way an odd roll can spur the imagination, but I do not believe that the dice should completely rule the game. (I don't even like calling them games, as it denotes a conflict between players of said game, and I do not like that attitude at all. As a GM or player, I am not against anyone at the table, and it is not a contest to be won or lost.)
So, when I run Rolemaster, I use 100's, 66's, roll-overs and roll unders - but I do not make the players roll a hundred tasks a session, so the unusual roll is unusual (not every session) and special and is treated as such. Also, if there is something that I believe is blatantly impossible, then they will fail, and no roll. (Unless I want to see if they make a complete a$$ of things.) If their skill is such and the difficulty of the maneuver is low enough, and they aren't being attacked at the time, I will rule that they succeed with no roll. (Like a master thief 150+ on Picking Lock, picking the lock to a chest in an empty room, no trap, no one trying to stab him, not hurried in anyway, etc... *Pop* in a few short seconds it is opened. There is just no reason - other than to make things take longer and to mess with the player - to make them roll that.)