I'm using a Leviton block, which I would think is an acceptable quality block. I'll try again and see what happens. I didn't have any bridging clips handy, so I made (used 1 long piece of wire, punched but didn't cut one one clip, then punched w/ cut on the next) jumper wires. Maybe they weren't punched too wel.

This doesn't seem like it should be rocket science. It Isn't, I;ve just gotta be doing something wrong.