Yeah I’m familiar with the Bristol scale. Unless these toilets have a bowl above the water I don’t see how it wouldn’t just flow down.

But either way, I’m not sure there’s a difference between loose stool on a shelf vs loose stool in water. I’ve had all kinds of stool in my life, and my share of bowel problems, and I’ve never had trouble analyzing my stool. A significant factor is just how it feels coming out, and smell is a factor as well. You still get the full sensation of both in a regular toilet, for better or for worse. (Two of my more interesting bowel problems were mystery unusual dark green stool (color-changing Oreos) and intermittent unattributable constipation (nearby cancer pressing on the intestine)).