You're right Bill, it does look like a crimp-on buttsplice connector. But (d'oh) if you look closer, you can see the edge of the yellow tape where it didn't stick.
Shouldn't phase tape be applied closer to where the wire enters the terminals -- in other words, right underneath it?
That way it's visible at a glance and not subject to confusion when you try to play the "what wire goes where" game?