It goes to show that if someone has a belief you cannot discuss things with them, because that have a belief. That belief encourages them to make wild assumptions and statements that support that belief because they need something to support the belief. To them it's logical and simple. How many times in the threads have the changes to armour, COG, installing new engines been described as 'simple' and 'obvious' and any evidence to the contrary more, or less ignored.
The evidence is irrelevant as they have a belief. When the evidence is against them, they often change the subject and ignore the unanswered questions. Partly because they know that they cannot supply the answers, but to recognise that would dent the belief and that cannot be allowed to happen.
You will notice that at the start of all this there was a recognition from P39 that the aircraft was better at low/medium altitude than higher up, which is true, it is better lower down. The problem was that he believed that it was supreme at low / Medium altitude which it clearly isn't. Now that has been proved beyond any shadow of doubt, he is now trying to pretend that it was better at 25,000ft, which a) it clearly isn't and b) Is contrary to his initial premise that it was better at lower altitude.
The belief that the P39N was some kind of wonder weapon ignores the fact that was little more than a twice around the airfield before it runs out of fuel fighter, ( a little harsh I know but you get the picture). The fact that a Typhoon could lug 2,000lb bombs further that the P39N can go clean sort of proves the point. I would expect the P51 to do something similar and the P40 probably has a better payload range. In fact the P39N doesn't really have much of a payload.
Why was the P39Q pretty much the last production version of the P39 if the P39N was so good?. I don't actually know the detailed reasons but we can assume it was because it was an improvement including the increase in fuel. The users were happy to accept the lower performance for those advantages, which tells me that there was something wrong with the P39N.