The first layer is the statistic of the average of 2.2 rounds being fired in defensive use of source situations.
I bought into this lie for years. It turns out that that number was mined for and that the data were manipulated. In fact, the number came from research that dates back to the 1960s, and the people who came up with the number only looked at the last ten years.
Even then, they were looking mostly at news stories that never reported on the number of shots fired. Even then, they included incidents in which no shots were fired.
So, the 2.2 shots number is a heaping pile of bullshit upon which the anti-2A people are trying to base their logic on capacity restrictions.
Still, even if it were true, the logic doesn't work.
A person facing violent criminals can't rely upon any assumption that the incident will be an average encounter.
Even if it were true that most acts of criminal violence were committed by one person against one person, which it clearly isn't, using this logic to restrict capacity would mean that any lawful firearm carrier would be left out to dry in any abnormal situation.
If a person can only carry "eight bullets in a round" (no, I won't let that go until Biden stops trying to take my guns), and he or she is attacked by several people at once, the government is responsible for prematurely disarming that person who may otherwise have had fifteen or twenty shots.