My 2011.5 did this the first couple of weeks I rode it. I don't remember, but it had to do with the electronics learning where 'zero' was on the throttle input.
I do remember my mechanic telling me to completely remove my hand from the grip, and shut the bike down using the main ignition switch vs. the button toggle on the grip. He said that after a little time, the computer has built a set of memories where the throttle input is most likely at 'zero', and the hesitation should go away on it's own. Still, quite the eye opener when it happens.
Either way, I didn't have the issue for some time after doing that, and of course once I got the TTS Tune installed... it went away completely.
I still believe, like others have said... this is something HD should be taking care of, and not something we on the road should have to discover on our own.
All of my stalls were while entering into a parking lot... slowing down to look for a good space, only to nearly drop the bike while at less than a walking pace... with sudden loss of power.