My title sums up my feelings on this issue.
Much ado has been made about open carry recently, but almost all the posts are stuck on either defending the 2A right to carry, or fighting against it on the grounds that it scares people (the Left's main argument, since there haven't been any open-carry incidents that the media didn't manufacture out of whole cloth).
Almost no one takes the next step, which makes it the moral duty of anyone carrying openly to be able to retain their weapon against a gun-grab (not a political grab, a REAL, physical, grab). This moral duty EXCEEDS the morality of your right of carry, by the way.
I wrote a few words on this over at Say Uncle, in a comment on one of his posts.
Just a little history here: Are you aware that in every hard-time prison in this nation are convicts who have trained themselves, and freely offer training to other convicts, in the skill of grabbing guns out of holsters? Convicts have a lot of time, and typically, they have two or three "yard" periods each day where they can go out into the prison yard and exercise in the manner of their own choosing. Several videos have been shot from the guard towers of such prison yards showing groups of cons practicing the gun-grab moves which they would use to take guns from "retention" holsters. They practice from the front, sides and back, and the open-carry citizen HAS to be able to defeat all these moves.
You defeat these moves by actual practice defeating them, with an experienced partner and a martial-arts instructor (who can be your partner).
It all takes a lot of time, even more time than learning to be proficient with the handgun in the first place. Defeating a gun grab of a slung long arm is even more difficult, I'm told (I've never practiced it).
People, this is nothing to mess around with. If you go out into a hostile world and open-carry (almost always with an UNLOADED weapon), you MUST be able to retain that weapon.
If you can't retain, don't open-carry. Don't even THINK about open carry.
It's just that simple.