The only places where a 4-way stop has room to make a roundabout are places where there is not enough traffic for it to matter either way.
The biggest obstacle is that there are just too many 4-way stops in urban areas where there is no space left to make a roundabout, you would have to tear down buildings. I don't think that is a valid argument in that scenario.
The more I look at that... Isn't that basically just a four-way yield, and the markings are mostly superfluous? You're basically doing the same motions in a regular intersection.
I guess that's the point, and the markings are just to give drivers the intuition of treating it like a regular roundabout (yield to your left [or right in the picture]).
> the markings are mostly superfluous? You're basically doing the same motions in a regular intersection.
The image linked, yes. However I've never seen one quite like that in the US. Instead where I'm at we have a small circular barrier in the center of the intersection (and some very eye catching reflectors) that you actually have to drive around. It's a very good design (imo) because it physically forces vehicles to slow down and swerve so there's no way to inadvertently blow through it at speed the way that sometimes happens with a 4 way stop on a long straightaway in the dead of night.
The space requirement is only slightly higher than the one linked above, still much less than a proper full size roundabout. It's basically a cement barrier sticking 1/4 of the way into your lane.
It's not necessary to stop if there's no car to the right (as this is left side driving), if there is but it is turning left, or if an oncoming car is turning left or going straight.
Yes. The markings are part of the road language. E.g. the X in the road with Keep Clear doesn’t actually do anything. It won’t keep you clear. You have to keep clear when you read it.
The biggest obstacle is that there are just too many 4-way stops in urban areas where there is no space left to make a roundabout, you would have to tear down buildings. I don't think that is a valid argument in that scenario.