Okay, now to write some clear things.
Something like a engine supported thieving is all in all possible i think, if someone writes it.
The learning if this skill, would only be possible while training with others. (Thievs guild). The rate of learning would need to be, really high, because you have a low amount of actions.
Of cause you can train with normal victims too. But they won't be happy about this, i think.
The problem while scripting is, the balancing.
Should the player be able to choose what he steals (really difficult) or not?
There could be a small chooing possibility. Like Money - small item - huge item. The bigger the item, the bigger the chance that the victim will be aware, that someone is taking something from him.
Then there is the RP problem, with such a skill. This skill would be only a engine support for RP. If the peoples start to steal without any RP, everyone will get pissed.
Nitram