Dan, I don't agree with you regarding this issue, I believe Michael R is generally open minded and will say what is, is. If you read the Wilhelm results it depends on what paper and type of photography you are doing as far as longevity (I'll admit most situations he has HP and Canon lasting longer) and the fact is nobody really knows how a print will look in 200 years and who really cares anyhow. If a print will last 5 generations I don't believe those 5 generations will be interested in the print unless it is worth something, for most here they will be worth a sentimental amount. Don't get hung up if print A will last 100 years and print B will last 300 years, that's like saying person A has $1 billion and person B has $5 Billion, it's irrelevant once you have 1.
I do believe that MR has tested and written glowing reviews regarding the Canon IPF Series and the HP Z series and I believe he has used both extensively for making his own prints. I think MR even started using a Nikon DSLR and proclaimed it to be the best. I believe that all of the BIG 3 are putting out great printers and it will generally come down to the user. If you like the Canon or HP printers buy one and then you can tell us your thoughts.
"I just don't think permanence for color is anything to write home about."
Why not? Your grandchildren will be dead and the print will either be in the garbage or still hanging somewhere!