Back on topic: it is possible - very VERY easily, to make a backup archive of retail install/individual Machine-specific restore DVDs, as I have copies of Tiger retail AND copies of my Mac Mini restore DVD set.
As for the for the people online who are so-called Mac "experts", but didn't seem to be able to figure out how to make a clone of the restore DVDs which INCLUDED the AHT (Apple Hardware Test) partition, I have this to say:
You Sirs, are idiots, not professionals. You just use DU and make a clone to a *.CDR disc image, NOT *.DMG!.
Just make sure ya own the originals, and ONLY bring the original discs out on special occasions... such as... the LOSS of the *COPY* that you use, day to day.
NEVER use the original restore DVDs to restore - make an archive copy, and use THOSE. Trust me, you will be crying into your breakfast, lunch AND dinner, if you don't.
Personally, I don't like thieves and certainly don't have any respect for them.
Just a question; if I go to an art gallery, and happen to have an EXCEPTIONALLY good photographic memory, and walk away having remembered (copied in my mind) the Mona Lisa, have I committed "theft" or broken copyright law?. lol.
Uncanny.