Okay, so... every original Print Shop disk shipped with a built-in backup utility which allows you to create exactly 1 protected backup, then deauthorizes the original so neither the original nor the backup could be used to make further copies.
The protection routine is tamper-checked, but this backup utility is not. And I discovered I could change 1 byte so it REauthorizes both the original and the backup it creates, so both can be used to make further copies.
No Gods, infinite masters.
This is the code that writes Print Shop's protection data to track $22. This code is read from track $22 then called by the built-in backup utility after copying tracks $00-$21. A separate routine exists that writes this code, and itself, to track $22, but by default the backup utility writes garbage instead. So the backup and the deauthorized master end up with the protection data but no code on track $22. This is why they can't be used to make further copies; they literally don't know how.
@a2_4am The funny part is I remember this disc being frequently copied by elderly schoolteachers when I was young with off the shelf disc copying software.
@gourd Copy II Plus wrote code specifically to reproduce Print Shop's (and Dazzle Draw's) protection data, then wrapped them in nice recipes (parms) that anyone could use. Before that, it was uncopyable.
Or your elderly schoolteachers had a cracked version. Wouldn't be the first time.
@david @gourd Looks like Copy II Plus 5.5 is the first one with the ability to make a protected backup of Print Shop. I just tested and it works. Looks like the same version has a similar parm for Dazzle Draw as well.