[SlashmanX]

> The "foot in the door" came from a seemingly obscure capability of the Dreamcast to boot not from a GD-ROM but from a CD-ROM. Originally intended to add multimedia functions to music CDs, the functionality called "MIL-CD" was never used much, accounting for a mere seven karaoke applications.

Isn't the first sentence of the "SECOND PROTECTION LEVEL" section exactly what you described?