I really don't know if this has been brought up or not but I was in a brawl with the dude in Markarth and I went into sneak mode. So... I started swinging for the fence, long and behold I started lvling my sneak. I went up 5-6 lvls in sneak by doing so. But I wanted to share this because I went on Wiki and didnt see anything about it!!!

I think it may be due to how sneak is leveled. It could be that dealing damage while sneaking levels the skill regardless of if you are detected or not. I know that doing damage while undetected improves the skill, but I have never tested to see it also levels sneak if you are detected.

If you wanted to, you can crouch behind any bartender amd sneak in to a brick wall all day to level sneak right up to 100.

I didn't know. I just noticed I lvled fast and few. Ive done a lot of sneaking and never lvled that fast and 6 lvls in a matter of 2 mins.