Nice demonstration. If I'm not mistaken that's Torbio Sensei taking ukemi for the first 1/2 of her demonstration as well. Personally I think that says a lot. I don't think I've ever seen an aikido instructor do that.
My teacher used to do it for each and everyone he graded for all of their yudansha tests. He does it less now but that's for a few reasons, one of which I suppose is that he's 65 now. The other is that he wants us (meaning the other yudansha and instructors) to do it more as do we. For my shodan he was my uke for 80-90% of the test but I think I was one of the last to have that, from then on other yudansha and instructors started helping people test more.
He still acts as uke for the black belt tests but doesn't do the whole test himself any more. For our higher dan grades he often acts as uke for the testee for most of the test, so I expect when we have our next 5th Dan exam in a year or two my teacher will be the uke for most of the process.
I doubt that we're the only people who do things in this manner in the aikido world.