In WME, when I add a new road to the following road, then I pan whilst adding said new road, a duplicate of the original road (or two in this case) are created & sometimes deleted. Last similar post I saw on this was in cartouche in 2010.
This is the first time I've seen anything like this. I've noticed an occasional layered road when doing cleanup, but it's always a little short section, so I usually discover it because I get an error while saving. I'm going to have to pay closer attention the next time this happens and see if it's anything like what you showed in the video.
BTW, what software are you using to make the video like that?
I just had this problem happen to me today. I'm not sure how long the segment needs to be before the first road "splits" but this sure is obnoxious. Same situation as before: the original road is a single segment and this happens only when you pan a few times during the segment drawing.
The original segment is split into two new segments with different temp ID numbers, but the original remains as well.
I had this happen for the first time today. I didn't know it until I tried to add a road junction and save it. I kept getting the generic an error occurred message. Eventually I accidentally found the layered road and deleted it. Then I got the error during save but when I OK'ed out of the message everything had gone non-orange, the duplicate road was gone, and editing resumed normal operation. I just kind of scratched my head and assumed it was a synch error of some type and forgot about it until reading this thread.