FFXI is not bootable. Also it's not the whole game. It is heavily encrypted as well...
It boots from a program called "PlayOnline Viewer" which is encrypted and plaged with the nastyest form of DNAS protection ever conceived. You can think of PlayOnline as sort of "game OS" for Square-Enix online games. It provides FFXI startup, network access, anti cheating, access to payment page, friendlist services, E-mail, etc etc...
Due to DNAS, the thing is bound to the Disc-ID, PS2 serial number and HDD serial number.
ATAD patch from modchip doesn't work with it because it requires the serial number query commands from the Sony HDD.
And yes, once installed from the discs, you don't need the discs to boot PlayOnline viewer.
Other comment... Without a FFXI/PlayOnline account you don't ever get to see the game title screen.
SCPH-10000_GH-001 SCPH-15000_GH-003 SCPH-18000_GH-008 SCPH-30001_GH-005 SCPH-30000_GH-016(V4) SCPH-30001_GH-010(V4)
2xSCPH-10190, 2xSCPH-10350, 2xSCPH-10280
"**** j0 hackers!"
-Sjeep (As seen on TOXIC OS ELF...)