I came across this gem the other day. I was in the midst of a massive digitising session, ArcMap was being “slow” and my frustration levels were at a monthly high. I decided to spend a few minutes assigning keyboard shortcuts for the editing mode tools Edit Vertices and Continue Editing. What happened next just pushed my frustration levels higher – the shortcuts would not “assign”, no matter how many times I tried it, or what manner or key combination I used.
That GeoNet thread confirmed that there is a bug of some sort which prevents it from working properly. So I gave up, opened a blank mxd and carried on in there.