I was doing a run to SFO a couple of weeks back on the lovely new CM 737-9 (739MAX, however they refer to it) and was in BG1 at gate 20. I got there as they were setting things up for the 2nd screening, and so just stood where I thought the entrance would be. Got chatting to a guy from CA, who had been down in South America for a bit, he was also flying in business. He was asking what was being set up and I told him about the secondary screening, and how it was pretty much pointless as they do not look at the monitors, and just load up the bins with all electronics with no need to separate them, etc. After it was set up, they had everyone move in front of the other gate (20A?) to line up to use the machines, so everyone shuffled over. Myself and some other prefer access passengers stood slightly off to the left of the line, in the hopes that they would have a separate entry. They ended up not having any signage, but did allow us in first (I guess you have to be in the know for this, or you were part of the long normal line). Got through without an issue, being told once again to put both laptops in the same (small) bin. No 3rd check for laptops like there has been for me on AC to YYZ for the last 3 trips.

Once inside at the gate, 4-5 of us were talking about the California fires. After a few minutes one of the guys asked if this flight is going to Newark! Someone let him know that that was with United, and this was gate 20. He left to go to his actual gate, no doubt going through the same security once again. So yea, lackadaisical sums it up nicely for USA flights too, as all tickets and passports are checked at these secondary screenings. So they missed the different airline, different gate number and different city on his boarding pass!!