Rouhani is a master of nuclear deception and Iranian historical revisionism whose strategy is to get sanctions lifted while achieving the nuclear weapons goal to which he, Khamenei, and the rest of Iran's Revolutionary elite have been committed to for decades. To do that, he will offer enough in the way of nuclear concessions to stretch out nuclear negotiations into next year while insisting on the right to enrichment.
By mid 2014, Iran's nuclear program will reach the point of critical capability where Tehran will have enough operational centrifuges to break out or sneak out to a bomb in an undetectable way. As Rouhani approaches that point, he will let it be known that Iran doesn't want a nuclear weapon, the Supreme Leader has a fatwa against such a weapon, and Iran will only develop a weapon if it's threatened with continued sanctions and backed into a corner.
Rouhani will demand massive sanctions relief, which he will receive from an anxious administration desperate to keep Iran from a nuke. Then when the Iranian economy is stabilized and the oil starts flowing, Khamenei will give into his irresistible urge to break out to a weapon and test.
At that point, Khamenei and Rouhani will have achieved their objective of a nuclear armed Iran with a stable economy and regional dominance. The key to this success of strategy is to insist on the right of enrichment as nonnegotiable. Of course it has to be nonnegotiable for Iran: They can't build a nuclear weapon without it.