Is the computer actually crashing, or is the display just going dark? If it is going dark, then the inverter wires which run up the hinge are likely getting pinched. The solution is to take off the clutch cover, reposition the wires and possibly wrap them in electrical tape to protect them better, and put the cover back on.
For my TI yes it's actually crashing. The mouse stops and I can't ping or telnet into the powerbook any more.
During the reboot, when the screen is black, I know the OS is running as I can ping and telnet into it. Plus I know it's at the desktop because I can adjust the volume. And when I push the power button and then I hit the enter key I know it's shutting down. So I know it's running.
I check the pink and black cable for damage, but it's seems fine. No kinks or anything like that.