Yeah I had the TC shudder on my 81 Olds but not since then. You could get similar issues going into overdrive so had to determine if it was the TC or the overdrive that was causing the shudder. Back then they used to say to disconnect that square four prong plug at the trans but I do believe sense then, it is not a recommended method except to diagnose.
At any rate, if in fact it is the TC, I would recommend having it checked by a good trans shop or the dealer. If it blows apart, it will send particles all through the transmission that will require disassembly and overhaul. How do I know? Lots of miles, lots of transmissions.