Your explanations on glare are very detailed, but frankly they are just speculations on how a glare would behave in those systems.
No, what I'm talking about is how glare fundamentally works on any optical system. The mathematics of wave propagation are the same whether we're dealing with visible light, infrared, radio, or even sound.
You can make all sort of theories like this to explain what we observe, but without evidence or backing by a real expert, it's just speculations.
I was pretty transparent in saying that simple convolution with a kernel is speculative, and just one example of something like what is observed could
happen. But we already know it's glare on the grounds of extremely strong evidence, which my speculations here have no bearing on. The question I'm answering here is simple: can it be that a glare can change shape like that? Yes, it can be.
At the end of the day we have aviators saying they have never seen an IR signature like this before, and no directly comparable examples that shows an IR signature like this either. We need to accept we are left in the dark here.
Just the other day a commercial pilot on reddit posted a video of a UFO that turned out to be another airliner on a regularly scheduled flight, that just happened to look like it was stationary next to a contrail because it happened to move in just the right way for that to happen. He, as a commercial pilot, would (and did!) say he never saw anything like it. But it was just another airplane -- the number one thing pilots are trained to look out for. Sometimes, common things look unusual.
More to the point, we already have one example (in the Chilean case) of a glare imaged by a military pilot that turned out to be an airplane farther than he expected, so the idea that it's impossible for a trained aviator to make this sort of mistake is in contradiction with the evidence.
Putting all the evidence together makes this case incredibly puzzling, objectively. I believe it needs to be presented as such, and not as "debunked" or "mundane", something I still see all the time in online discussions (Twitter, Reddit etc).
From a scientific perspective, we don't have to show that it's "mundane", though of course it's very satisfying when a case admits a complete resolution. What matters is; does this case admit only
an extraordinary explanation, or could it be a confluence of ordinary factors? What I mean when I say "defeat that line of reasoning" is not about winning internet debater points, it's about whether or not the evidence is sufficient to reject the null hypothesis that this is an ordinary airplane doing ordinary airplane things. I'll have more to say on the other thread, but to stick to the topic here I'll simply ask: is there anything about this glare, whether its shape (and change thereof) or its movement that's impossible to realize with a jet engine?