Yes i have done this but what baffles me is that this particular paper, which is matte, uses both MK and PK. This is what is confusing to me. On all other matte papers i use i didn't upload the AM1X file and just chose a Canon Fine Art base paper that only uses MK. My results have bee stellar. So now I have tried the AM1X file upload route and apparently Canson suggests the use of MK and PK.
I don't have a 4000, but I do have an iPF6450. What you're suggesting about the profile using both black inks does not sound right. It's going to be one or the other. Also, I don't think you have installed the AM1X file into the Media Configuration Tool because the media type in the printer driver window would read something like "cifa_iPF4000_edition310" (you have to toggle the media type field to see it), not Canon Fine art Textured.
Just as an aside, where are you seeing "Canon Fine Art Textured"? Installing the icc profile is different from installing the .am1x profile into the media configuraton tool. They are two separate processes.
Have you actually run the Media Configuration Tool software and uploaded the am1x profile into that tool? There is a .pdf file buried in the Canson zip file explaining how to add new papers to the Canon Media Config tool.
Are you running Windows or Mac?
Patrick