I find the best way to do this without getting caught is to grab this first item and close. then go in for more. The longer you search them the greater the chance of getting caught. Also you can use some pickpocket potions that can help a great deal.
That would actually make sense, but it's news to me. I think the whole pickpocket thing would be cooler if the bounty wasn't automatic. Like, if you got caught, run! If you can hide before a guard gets a clear look at you or catches you, you're home free.
The problem with pickpocketing is that it's pretty easy to get caught, and the consequences if you do are extremely harsh. Now, granted, you shouldn't just be able to walk up and steal a giant sword off a guy with ease either, but then, this is a video game.