Some people have many EEPROMS. Is it because EEPROM is easy switchable on these development cartridges ?
Does it mean that development encryption is ok to be used on a retail console ?
But you said above regarding IS-NITRO-EMULATOR that you can use a development cartridge on a retail DS. Is retail DSi very different in that case ? Not sure to follow here.
Almost every cartridge flashed with an IS-NITRO-EMULATOR will be usable on a retail DS (I say almost because I'm sure I don't know everything and don't want to take the risk saying that 100% will be compatible on retail hardware).
Since the retail DSi used like the development DSi a encryption key yes it's very different. It's pretty simple :
-Can't use retail TWL game (all twl game are marked like that "twl-xxxx-usa/eur/jpn on the cartridge) on development DSi
-Can't use Development twl game (flashed by a twl-emulator) on a retail DSi
And you can't use some nitro development cartridge on a retail DSi, but the cartridge will works on a retail DS (fat/lite) and on a panda.