While I understand your points, I respectfully disagree.
Here's why:
The fact is while a certain amount of reduction is viable (4k to 2k) without a massive loss of visual fidelity, a large amount of reduction (4k to .5k) will result in an enormous loss of quality.
The same applies when trending upwards. Bear in mind, that when using post effect filters, this is MORE pronounced because there's more pixel depth to work with on the actual texture in question. So here:
(without reshade, left side is a seam of the standard res - right side is the higher pixel depth/sharpened texture)
(with reshade, left side is seam of the standard res, right side is the higher pixel depth/sharpened texture)
(left side completely stock texture, stock gameguru - right side reshade HDR level 2 and sharpened texture).
It's important to note...
This is NOT 4k resolution. It's a fraction of a 4k texture. More realistically this exercise was bringing up something from .5k to 1k.
So you're going to see a moderate improvement, but nothing massive. Improving it further requires going even larger. At that point, yes, I'd reskin the model. Now if you don't see a difference, that's fine, but I'm not going to argue the point any further. I made my post, stand by it. I don't make money from these posts; I do my level best to properly inform the community (what's left of it) of things that can be done to hackney this half-built engine into something reasonably useful. There's only so much that can be done to dress up a pig here, fellas. And at this point I'm assuming a certain level of perfectionist that yes, even a slight change from a jagged set of 512 bit depth pixel to 1024 bit depth pixels matters. And I'm that type of person. So I wrote the article in the hopes that others, like me, might benefit. I tend to notice the biggest changes when going two orders higher, say 512k to 2048k. That requires a lot more fiddling and usually a little hand-modification of the texture, which of course this article was supposed to open the door for people to that line of thinking.
If you have more to say on it, by all means. There's a lot of other pieces there that you've flatly disregarded as well - such as changing the plainly pathetic specular mapping to something more functional and realistic. On this point though, I won't discuss any further; I don't feel like we're going to agree or sway the other.