Diplomacy is always conducted on a lower level no matter what world leaders might say for the crowds. World leaders speak for effect and in an attempt to influence diplomacy. That's just the way it works and the way it has always worked- why do you have a problem with it? It sounds like in this case it worked out well.

What we don't do is send the US President over to meet terrorists, the heads of rogue states, or potential and real enemies without preconditions- and usually a virtual agreement in hand- ahead of time. Other countries do the same- you don't see Merkel or Sarkozy trotting down to Iran or over to Venezuela, do you?

But I'm sure Obama will change all that...