Um, it's not really a good anology. It takes away from the authenticity of going the thief path. Alteration already gets plenty of gadgets, thieves have a single skill dedicated just to this.
Yeah but spells make noise and attract attention, lockpicking doesn't. Lets hope Skyrim can detect alteration spells unlocking a door as a crime unlike Oblivion. One thing I'm disappointed with about lockpicking is it isn't in real time, AFAIK. That would be awesome if they showed an anim like alchemy/smithing etc where your character is fidgeting at the door with the lock picking mini game sort of off to the side or something... then a guard came up STOP RIGHT THERE CRIMINAL SCUM!!! and scared the living bejesus out of you.