I think you are completely right Tikal. All we really have is anecdotal evidence, on both sides. (As someone once said, enough anecdotes do eventually add up to a statistic, but we are far from that point.) As you point out, there are significant factors distorting and prejudicing the evidence. What we can say, I’m confident, is that it is possible to use WVO successfully, but it is also possible to have major problems doing it.
I have long been rather curious about why some conversions go so well, while others do not. Is it the oil, the filtering, the WVO system on the car, user error, carelessness or some combination of these? I had hoped we would find the answers on this and the other forums, but I now suspect that will not happen. As the suppply of suitable cars dwindles and people seem so much less interested, it will probably just fade into a tiny niche. That, of course, will make some folks quite happy.
It was great fun while it lasted. Could there be a book or a cult film in all this? Ah, I doubt it. Too bad.