This worked on my wife's G2 LS980. I had already tried adding pressure to the digitizer connectors. I took the electric starter and unbolted it from the side burner of my gas grill. It has a pretty sharp tip on the end of it. I set a towel on the grill to set the phone on. Right now she still has a screen protector on, but the dead zone of the bare touchscreen was still exposed on the edges. I touched the tip of the electric starter to the exposed part of the dead zone, phone on - screen off. I fired the starter. At first this didn't seem to do anything, but after about 5 attempts, it worked. The screen was 100% responsive, no dead zone, and the knock on began working. No reboot or anything else. I will post back how long this lasts.
Edit: It lasted about an hour. I may try it again.
Edit: I tried this several times. It only lasts a short while. But during that time the touch performance is superb.