Technically everytime the crank turns with the battery disconnected you need a case learn, and they are hundreds of members that have never had a CL done after that.
Tranny removal/instal, CPS change, PCM change, engine pull, ect......
That was my point, there are about 33 reason to get a CL done, and most dont think about it. Just about the PCM change.
And if your PCM has the removable knock box (like 97 GTP), you dont need a case learn at all, when swapping PCMs as long as you nswap the Knock box from one PCM to another.