macmikeman said:
I will have to butt in here and say that I find the side pressure plates that are supplied with most of the common grade GFI receptacle outlets to be sort of inferior. I make sure to screw it in really tight and pull the wire to make sure it is seated in there good, but have still had a conductor slip out after tightning it in.
Coincidentally, I ran into this just this week. I always use my drill when trimming, and I started to suspect the phillips-tip was skipping out before I got a decent torque on them.
While I always give them a quick tug before moving to the next screw, this time I rotated the receptacle once (as in, turned it ground-side-down to install it), and then stopped and brought it back out and rotated it back for one more tug. The wire came out.
I'll continue to use the back wire, but I'm using my flathead screwdriver to finish tightening the screws from here on out. I had one of those "how many of these have I installed poorly?" moments that sunk my stomach a couple inches.
I'll hold comment on some of the other methods until more votes are in.