Honestly, why bother? You'll get plenty of sneak just by sneaking around doing missions. My advice is don't grind any non-crafting skill, there's no point. Buy training in your armour of choice, and let the other skills increase naturally. You'll have a lot more fun.RE: Raising Sneak. I'd like to confirm that the method of sneak-attacking an unkillable character works, within certain limits. I did it to the Silver Blood guy as part of the Forsworn Conspiracy chain in Markath. There can't be anyone else that sees you do it, however, and it isn't as fast as some people suggest it is because you have to wait for them to reset before you can sneak attack them again. It was good for over 30 skillups before I just couldn't grind it anymore without my eyes bleeding
Really, any weapon type can be made absurdly super-powered with the benefit of smithing. The daggers aren't special, in fact I prefer Sword/Dagger to them because the dual-wield power attack animates so much faster, plus the reach on the sword makes stand up fights more fun, at least for me.In other news, dual-wielding two Daedric Daggers that are max-improved is just nothing short of crazy, even unenchanted and without all the perks. I played around with not surrendering during the Forsworn Conspiracy chain and just ran through town killing guards when they tried to kill me. It wasn't a fight, it felt like playing Pac-Man without the threat of the ghosts frankly.