You may need to educate me here. Yield, in every instance I've ever seen it, has to do with a binary situation, and one roadway always yields to the other.
Example: Two lanes merge into one, as in a divided highway onramp, and the right-turning lane always yields to the left-turning one, such that left-turning traffic is never stranded in the middle of the originating roadway.
If there are yield-right-of-way rules at a four-way intersection, I do not know them, nor do I think it would be a good idea to dare people to think they have the right-of-way tucked in behind another car. Who was "at the intersection" first? Have you ever seen when traffic lights go out and they all flash red at a four-way-stop? LOL, that's like saying "whichever road has the most aggressive assholes when this first occurs is going to have the right of way until the cops show up to direct traffic in 45 minutes." Not quite an exact analogy, as that's supposed to be a four-way-stop, but this is what people do with a slight bit of ambiguity even in a situation that theoretically has none. I consider myself an educated driver, but I don't know how a four-way-yield's rules would work.
A stop sign works because it has no ambiguity. I think you'd have a lot of situations where two drivers would be approaching an intersection roughly at the same time, both could see each other, and a game of chicken would ensue with each gunning to try to get to the intersection "first."