One could conclude from your comment that you think Iran's nuclear program has been on idle because of the negotiations. The experts have been saying for at least the last four years what Iran was doing and intending. Now four years later we are qibbling about whether they could break out in 6 months or 6 days.
According to the Iranian objective or any other measure that is significant progress toward their goal of being a nuclear power/threat.

To qualify their pace of forward accomplishment to aquire a nuclear weapon, based on whether or not these negotiations fail or not is extremely naieve.
Just listen to the Iranians. We will not be denied a nuclear capability. We will not stop nuclear research and development. We will not accept an agreement until the sanctions are lifted. The Ayotallah has said there is little that he trusts about America.

Apparently some folks need a brick house to fall on them including Obama.
The Iranians are sabre rattling not just at Israel but now due to our weak stance he is now blasting away at Obama/USA.

The negotiations have nothing to do with the past development pace or the current pace of evolution of nuclear capability.

What is it the police negotiators always say.....keep them talking while we get ready.....Ayotallah obviously watches television as well. Obama is out of touch. His advisors are doing him absolutely no good at all. No doubt because they know where he is headed.

Iran's nuclear capability will most certainly be Obama's legacy. Yes, he will be noted for assisting Iran accomplish THEIR objective.