On paper, the Canon PRO-1000 has better features than the Epson P800, except for the paper size limitation.
More inks, then more gamut, vacuum system, then more print precision and ease of loading.
However on the conclusions of the test, especially in image quality, I not detect a great enthusiasm for the Canon.
Why?
It surprises me.
I don't know what script you are reading from, but right at the beginning of my review of this printer I said the following:
<<In a nutshell, we think it’s a fine printer with a lot going for it. It has every appearance of being a very solid machine,
the print quality is superb, the in-built features are most interesting and the user-friendliness is very good.>> (emphasis added for your convenience).
In the "Wrap-Up" at the end of the article I said: <<The Canon image PROGRAF PRO-1000 delivers excellent print quality. >>
Is that not clear enough?
Now, referring to remarks further up in your post, please note that more inks does not necessarily mean anything. It depends on the image and what you are measuring for or looking for. "More gamut" also within a range could mean very little or something, again, depending on the image and the treatment. Not clear what you mean by "more print precision". Looking at the table below Figure 7 in my review, the average dE results for both the P800 and the Pro-1000 using custom profiles are competitive. A difference of a few 10ths of a percentage point on a test like this is insignificant. I agree with you that Canon scores higher on ease of loading, but I would add that one doesn't need a PhD in gymnastics to load a P800; Epson scores higher on paper sizes.
Overall, I think these are very competitive printers from an objective perspective, and you need to read more carefully. There are some feature and operational differences between them, hence one should select a printer depending on which feature set and operational factors are more relevant to one's own requirements.