I was waiting for that. So your attacks on those who used and know of the background of Ilfochrome Classic are largely indefensible. Sorry. They are. You made it clear in the last few words. It's just a hobbyist making a finding and putting those findings on a pedestal compared to Wilhelm. Drrrrft. Read what Drew said. You're having a hard time countering some facts, yes?...
Why were you waiting? The trial description has been sitting in this thread since post #9. More ad hominem. "Just a hobbyist." Wilhelm on a pedestal? You've denigrated his results too. Facts are facts. Methinks you doth protest too much.
..."Typical consumers"? Oh my. The big twisters of all sociologists...
Why do you have trouble remembering that Cibachrome/Ilfochrome prints weren't just sold by big-time photographers to "collectors" but also marketed as unexposed 'paper' and associated chemicals to those working in home darkrooms? Prints made at home by "typical consumers" were displayed in places frequented by "typical consumers," not under controlled-spectra illuminants as specified by the gurus you've referenced in these threads.
...What else was in your office that could effect [sic] prints?...
There was nothing present to make either Cibachrome/Ilfochrome prints. If your question was intended to ask what might have
affected prints, anything there had equal opportunities to work its fading magic on both Cibachrome/Ilfochrome and RA-4 samples.
...If your hobby is to attack photographers who produced their work to Ilfochrome Classic, you have a problem underlying that type of thinking. So we can see, evidently, you sneer at Ilfochrome Classic and sneer at photographers producing their work to it ('cause you don't like it), but your slight is based on your own odd, rudimentary experimentation with no solid review. And you're trying to shout down established fact? So your findings are easily dismissed...
I have no attack-related hobby. The posts I make at APUG in response to those who would perpetuate the myth that Cibachrome/Ilfochrome prints exhibit better stability on display than modern RA-4 prints are solely to set straight any readers who might be misled. My dislike for Cibachrome/Ilfochrome surface gloss is a completely subjective personal aesthetic opinion which has no bearing on print life expectancy; mention of it is included solely to entertain Drew, who loves the shine.

You may, of course, dismiss Wilhelm's and my findings. Other readers ought reach their own conclusions.
...I must ask you, what did you expect photographers to use when that (IC) material worked so well for the intended purpose — of showing off the best of a photographer's work?...
I had no expectations in that regard. Every photographer was and is free to choose whatever media they deem appropriate for their own work. Nothing I've posted implicitly or explicitly criticized anyone on the basis that they made such prints before Cibachrome/Ilfochrome's poor light-fading performance should have become known to them.
And what's this about "promoting sale or resale of Ilfochrome prints?" When did we promote the sale or resale" of it? We photographed. We produced. We printed. We sold. Just like brush artists do with their work. And it was not just IC: a variety of giclée was produced too. It had to be. The market being catered for required variety, but first and foremost the market desired quality imaging. When did I bang on to a client about Ilfochrome Classic as being a pot of gold ducats? My job was, when commissioned or producing my own work, to first and foremost, make the image. The print was secondary, but it had to be bloody good for the cost of all of my work (the IC printing was a small part of the overall fee structure)...
You've previously referenced a number of photographers who offered Cibachrome/Ilfochrome prints to collectors through galleries. While your work might have been on commission rather than speculative, collectors buying prints through galleries for "investment" expect that what they buy will last and that, should they want to re-sell it on the secondary market, materials used have a reputation for lasting. Without arm-waving specification of spectrum-limited illuminants, the display life reputation of Cibachrome/Ilfochrome is in jeopardy. Again, methinks you doth protest too much.
So you consider such unscientific results to be valid when you report them...
but you reject other folks' reports of their own experience under identical uncontrolled conditions.
That's rather self-serving, no?...
No. It can't be self-serving since I've never purchased an "artist's" Cibachrome/Ilfochrome print and therefore couldn't re-sell one. I have no dog in that fight.
I consider real-world results under typical consumer conditions to be more useful to "typical consumers" than any controlled lab tests replete with assumptions and approximations. Before you invoke your credentials, note that I take this position as a degreed engineer. Just like you.