The jumping-on of shit is the thing I like least about cats. Except the allergies thing. That's the thing I like least.
It's easy to train a cat not to do this. I just have a cat-safe room, and it is so small I figure I WANT her to be able to jump on things so she can get exercise.
But when dogs jump on me I do not like it. Maybe it has something to do with the fact most of them drool and some have a habit of eating their own stools. It seems dogs are always wet-feeling on their feet, even when they aren't.
If I were allergic to cats, I'd be one of those people who would have one anyway, and just sneeze all the time.