Forgive me the following long text. Just blathering away a bit. It goes off-topic, but is somehow still relevant for PS1 homebrew in general and Tonyhax International in particular.
Of course it is possible. It has been done. Unfortunately I don't see a way with consumer equipment.
After all this years Datel should spill the beans
how exactly they did it. There is no harm for either Datel or rights holders of PS1 games. The latter are out of production for eternity and can be pirated in numerous ways. It is not that this knowledge would open a previously tightly closed gate.
Quite the contrary: I see plenty of legal possibilities. I mean there are new commercial Dreamcast games using the MIL-CD loophole. Producing unlicensed (not licensed by Sony) discs of homebrew software would be nice. There are new releases for NES, Game Boy and the like on cartridges.
Just that d*mn SCEx protection is preventing new PS1 discs.
Regarding Tonyhax and similar software unlocking the drive: They can and will be interpreted as piracy tools. Realistically speaking it is true. Just look how often people use the word "backups" (putting it in quotes) as an euphemism for illegal copies (opposed to legitimate backups when owning an original). With that argumentation Nintendo successfully outlawed R4 cards – despite many legal areas applications:
Can be (ab)used as piracy tool → 100% just a piracy tool
Not really. CD pressing is not expensive. Some companies offer starting as low as 100 copies for creating a glass master with a total cost of about 300 to 400 Euros (master + 100 copies). Once you have the glass master each produced disc is penny article. It has always been like this. That is why N64 games were so much more expensive compared to PS1. The financial risk of not selling enough N64 carts was also way higher than not selling the whole stock of a PS1 shovelware title.
It would be easy enough to sell one key disc for about 5 Dollar/Euro while producing them for pennies. Problematic is the legal problem: I wouldn't dare to
sell an unlocker (or just contact a CD pressing plant for such a task) because fearing to get f…ed in court for piracy business.
You never know what happens. Just look at eBay. It is full of obvious piracy ("reproduction cartridges" as euphemism, R4 clones loaded with several 100 ROMs) and nobody seems to care. I bet if I was to even think about doing such a thing (which I wouldn't), the police would knock at my door a minute later.
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What follows from the long text? It would be so nice to find a way to do it at home. But the thing is a beast. I've read through the patent (which seems to be full of OCR errors online) and it is just a general idea. Just a few buzzwords connected in an intelligent looking way… and there you have it:
Patent worthy invention. The underlying idea is ingenious though, as normal consumer hardware is thoroughly unable to even gather the tracking data – let alone reproduce it.