Your -2 comment score leads me to believe some people didn't get your joke. I'll explain it, which we all know will make it funnier.
The previous comment mentioned their observation of half of the traffic moving through right on red and, later in parentheses, said this was based on n=1, i.e., based on the observation of a single vehicle. I'm 100% certain that was a joke.
The follow-up comment was also certainly a joke. They're pointing out that the commenter observed one car and then made the claim half of cars use right on red, so they're jokingly asking how exactly half of one car made it through.
Get it? Now stop downvoting the dude, stats are great, stats dad jokes are better.