the question deserved the response it got, as a consequence of it's utter naivete. how are the iranians supposed to know what the americans don't want them to do? yeesh. the subtle propaganda in the question isn't the idea that the iranians are malleable to american influence - for in truth they are, and anybody that knows the situation knows this (despite matt's enforcement of the axis of evil narrative). rather, the subtle propaganda is the idea that the iranians can somehow get out of the situation they're in by playing along - that the americans are reasonable actors in the conflict, driven by rational concerns and a desire for dialogue. ask ghadaffi or saddam or even assad how well that worked out.
it's not a question of whether the iranians care about or know what the americans want. it's a question of whether the americans care if the iranians are being co-operative. the answer is they don't.
and i'd have laughed at him, too, if i were her.
http://www.youtube.com/watch?v=azDkOcIvxHk
the "incentives" driving the sanctions are not to change the behaviour of the regime, they're to try and incite the population to revolt.
this ends one of two ways...
1) the regime is overthrown.
2) iran becomes a russian protectorate.
....and the "detente" driving talks is a reaction to the increasing likelihood of the second option, not something coming out of a desire to bring the iranian regime back into the international community. on that point you have to give the obama administration a little bit of credit. that's something successive american administrations have not really taken seriously.