I'm just reading and learning here, but it seems like where things go sideways is people talking about slightly different things. To my read, this test showed that good barrels don't meaningfully shift POI when hot. Of course my goal in the field is 1 or 2 cold bore, but I'm not going to zero with 1 or 2 for reasons discussed at length elsewhere, namely that 1 or 2 aren't enough to show the average POI, which is what I'm trying to adjust. So, I can get a decent sample size (10 shots) all at once, instead of doing 2 a day for a week or something, and the results will be the same.
Put another way, even if all you care about is the 1st cold bore shot of the day, you need a good zero to do that, and this test shows the fastest way to get there is to just rip 10 at once.