The only thing I have seen that remotely comes close to your description is a trail crossing in Prince Georges County in Maryland. I believe it is on the Northwest Branch Trail crossing US 1. While cyclists do have a stop sign and the cars do not, there is a sensor (two vertical posts) that when a cyclist passes through the sensors embedded lights along the crosswalk start to flash. So far in my experience has resulted in a high compliance of motorists stopping and yielding the right of way to cyclists. So the net effect is more like a yield then a stop for trail users. The only problem now is trying to get more of these things installed.

I don’t have any numbers but from observing behavior from both cyclists and motorist this seems to be the safest busy road crossing of a trail that I have seen and it is the most convenient for trail users.