Kahneman hedges just a bit in his talk: " To a good first approximation, people simply don't change their minds about anything that matters." Trying to explain the small number of people who do change their minds, David McRaney has an interesting book out called How Minds Change.[0] And I imagine there are people who change minds, even outside his model. People who change their minds when it doesn't seem to help them…
I've seen a strange case, where someone argued blindly, but the next day advocated for the change. He didn't say it was his own idea but he didn't told he changed his mind :)
If you're arguing for a course of action, answer the objections well and then drop it. Often the person arguing against you (especially if they're "the boss") will come back a few days later and present it as basically their idea.
People get emotionally tied to what they came up with, and it can take a few nights to disconnect enough to move on (even if they never admit they were "wrong").