Even A-B-A is counted as “two trips” which immediately doubles the number of trips and halves the distance of each. I have no idea what the rates of A-B-A versus A-B-C-D-A trips are, but their methodology here makes the entire study seem almost pointless, at least when trying to gauge the average mileage people are driving per day in reference to EV range.
Even using average yearly mileage can be misleading as almost nobody drives a fixed number of miles 7 days a week. I have a fairly long commute at 100 miles round trip, but my average daily mileage over a year is only 60 miles, or 60% of what I actually drive when I’m going to work. Someone telling me that a 120-mile range vehicle would work just fine for me based on my daily average would be completely wrong in that assessment when you account for efficiency losses and extra load from things like highway speeds, using the heater, or me having to make side trips somewhere on a work day.
I wouldn’t pull too hard as it might just be a proprietary slot like the other user said. The plastic around the plug looks like it could be easily ground off with a dremel tool and allow you to use a normal extension cord.