This does work, because I have tried it before, but there are a few things you have to make sure of first. 1) You have to make sure that somebody or a creature is around you in order for your Sneak skill to go up at all. If there's no creatures or people around, you Sneak skill will always stay the same. 2) When you're sneaking around somebody, make sure that they cannot detect you. If you're detected, your Sneak skill will not go any higher. 3) If you aren't an Expert of Sneak already, when you level to become an Apprentice / Journeyman / Expert, the screen comes up that says that you have become an Apprentice / Journeyman / Expert so you cannot move from there on out. Though, when you start this and you're an Expert already, this shouldn't be a problem. I would suggest trying this in the very beginning of the game around the rats, in the cave you start out in. When you're in the pure darkness and you're sneaking into a wall, chances are, the rat won't detect you easily. I found that this worked with the rat that wouldn't attack you after you defeat your first Zombie.