No, drivers/cyclists/pedestrians completely lack understanding of the rules of the 4 way stop. The only predictability is that they're all f'n goddamn unpredictable primates, who will scream and fling shit at the first sign of trouble at a 4 way stop. Coming to a complete stop has nothing to do with it, because already the vast majority don't even realize that the complete stop at the stop sign line is how order is determined. Most think it's who arrived in the vicinity of the stop sign first, or it's the person "to the right", or they simply don't know or give a fuck and creep out waiting for a horn to tell them otherwise. Both middle finger and brake foot are on trigger alert, because they don't fucking know shit else.
The majority suck at the 4 way stop. They are predictably stupid.
Overwhelmingly, more than 3/4 of the time, as a cyclist coming up to a stop sign, cars do either an "oh fuck go now!" before they've completely stopped, or "oh fuck stop and don't move til he leaves" maneuver. It's panic. That's the rule. I have to either go through the intersection out of turn, wait a long long fucking time, or engrave invitations to cars to get them to go. And because I live in a state where tinted windows are legal and somehow common, I can't see shit about the other driver. Sometimes I think they're waiving at me, but they're too stupid to realize I can't fucking see them.
So that's how it really is. It's not like the current reality is unicorn shit where everyone gets along happily, follows the rules perfectly, and it's this one Idaho Stop idea of cyclists slowing down (a lot) but not having to completely stop, which is going to create chaos. If anything it will reduce it. Somewhat. Except in some cases when it doesn't.