You're trying to rewrite the laws of physics. This is simple physics...and simple math.
You come across as a very knowledgeable person so you must know already that the laws of physics and reality are two different things. Math is not an absolute answer to anything. I don't care how much number crunching anyone does, math and physics do not provide an absolute answer. They are abstract no matter how you cut it and with that said there are always variables that exist which are not within our realm of computation. Math and physics will provide a basic guideline and either one can be twisted just enough to glean an outcome that one desires. You basically said all this yourself when you acknowledged that you take multiple samples and average them however you and I both know it is beyond just human error alone.
You also stated that the tire with the smaller contact patch will have a higher psi. I then showed two tires that I own which refutes that statement. It is an actuality. It is a real occurrence and it did not take math or physics to show you this yet your precious math is allowing you to disagree with physical evidence that is directly in front of you.
Of the two tires in the pic, the left one has about 2500 lbs on it at the moment. Once I lighten that load, and at your request, I will gladly present to you the egregious differences in the contact patches on what are supposed to be two 205 tires where the one with a lower max psi indeed has a smaller contact patch.
As I stated earlier in the thread, I race motorcycles. I have a Honda CBR600. I have gone thru a few different tire mfg's as well as changed sizes of tires. Even with the exact same tires mounted every race weekend, I am constantly adjusting the suspension and air pressures on that bike, albeit within a general baseline, in an effort to achieve certain handling characteristics.
The most recent time I changed tire mfg's, I tried to use the (then) current suspension settings. I found the chassis to give completely different feedback. I had to reconfigure the entire bike from front to back regardless of the fact that I had the same size tires mounted as the previous ones I was on. I found myself running different baseline tire pressures on both ends of the machine. That alone told me that, while tire sizes can be the same based on what's stamped on the side, the contact patch and tire behavior is drastically different.
You can throw articles at me all you want. You can do all of the math you want but none of it means anything because none of it is an absolute answer since atmospheric changes are happening with every breath we take…changes that affect how a tire contacts the ground.
A 215 from Tire company A will have a different contact patch than the one from Tire company B, even if they are subjected to exacting scenarios.
This is the last time I am going in circles with this conversation. The way a tire company construct its tires, sidewall stiffness and carcass flex...even the compound....has everything to do with the contact patch as well as what happens to that patch when other forces are put on it.
As far as that last article you posted, because someone chose to call something a "bible" does not make it so and there are so many holes in that article I'm not even sure where to begin.
Just this right here is erroneous:
"Well because the narrower tyre has less capacity for cooling off, it
needs to be made of a harder rubber "
It
absolutely does not "need" to be made from a harder compound. Heat is very easily controlled thru tire pressure.
Speaking of bibles, this post right here is also a bible and on that note, I'm done.
Just know that neither of us are right but neither of us are wrong, it depends on nothing more than one’s perspective.