Not sure the criteria don't skew the result.
More than one citizen have had their gun taken from them and used against them, albeit rare but it has happened.
CITE CCW holders, gun shop owners handing a gun to a fake customer and even dope deals gone bad have all resulted in such situations.
CITE I would have to say that elimination of police is an acceptable criteria since they intentionally put themselves in close proximity to known criminals effecting arrest, but why the security officer? Seems to me since they typically have no authority beyond that of a regular citizen they should not be eliminated from the criteria. When you adjust the criteria to eliminate a majority of persons participating to alter the result it seems like the political game of the anti's.
I am not sure what the actual numbers are of OC'ers that fit within the criteria, when compared with the population of the USA posed against it, it likely is not too far from the percentage you have in the quote above. If it gets adjusted to include firearms openly carried in vehicles then pointing out the number of rifles taken from the gun racks in trucks should count.
I understand that it is to refute the "someone can just grab your gun" argument against OC but altering it to suit is not unlike the officers claim in the article. His claim that he can grab your right wrist, pull it to his chest and usually disarm is likely accurate. He leaves out the part where he trains regularly to do this and it is part of his training program for police officers to disarm combative armed suspects. I believe it to be true that most criminals do not drill on "disarming" some might.
When you consider the average security guard gets nearly no training I think it puts them into about the same category as the average OC'er and thus should not be eliminated. The biggest difference in the two, the security guard is more likely known to be armed vs the average OC'er would likely state very few people even notice.
My point: The "move to a softer target" is a more sound debate point and does not give the impression that training would be a waste as it is not something that happens.
Opinions vary, that one is mine, others will have theirs