The region code is signed as well. To achieve regionfreeness, unsigned code must be allowed.
I would wonder, however, if it would be possible to make patches for region-free games, or at least their region counterpart. It would basically involve injecting different signed code, but afaik, the signature goes completely through it, so it's not just a simple byte change or anything.
Do what I did; get a NTSC/J console. Play your Japanese games, and most of the American games (IMG:
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