Do Europeans have a knack for underestimating evil?
Does Europe's chief negotiator think social intercourse is really what is important about talking with Iran? Perhaps Iran will not have time for nuclear armament if she keeps it busy talking. Just days into a new agreement with Iran, which already drags the clock out for more time to talk, Europe's chief negotiator is suggesting the six-month time frame be substantially lengthened!
Now, even if you think, like Catherine Ashton, that six months is too short for these negotiations -- which would put you one thought above an empty head --  why would you want to take the pressure off  by talking about an extension the second the clock on the first extension begins to tick? From a negotiation standpoint, open talk about extending the extension is like your bank telling you, "You've got six months to get your mortgage payments fully out of arrears; but, if if that doesn't work, you have twelve."
How does backing off the pressure engage someone to correct their problems quickly? Is Ashton trying to give Iran hope that it can drag things out even longer if it plays the game, or is she just naive enough to think that time, itself, isn't dangerous here? Perhaps she missed the interview on Iranian media in which the Iranian president openly bragged about his brilliantly successful plan of dragging out negotiations  in order to buy Iran more time for nuclear development.
Europe has a top-level negotiator who doesn't know the basics of negotiation
Conversation about extending the extension as soon as it begins -- if such talk has to happen at all -- should only happen among the P5 +1 negotiators, never in public, and never a word of such hope breathed to Iran's negotiators. Then, when the deadline has nearly arrived, if Iran is close to something that starts, at last, to look like a real deal and more time is needed to iron out a final detail or two, THEN is when you could hint to Iran that more time MIGHT be possible but only in exchange for a little more concession on some lesser sticking point. You never give away time for free in these kinds of negotiations.
Doesn't Ashton know there is nothing like a ticking clock to keep pressure on a reluctant negotiator. The P5+1 have already reduced pressure on Iran by reducing sanctions to show good faith. She must be hurting for them because of the pressure they're under. Poor Iran, having to negotiate under all that strain of a new half-year deadline.
I guess some people  can't resist being seen and heard and like to look noble and generous.
Suggested reading for Catherine Ashton:
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