CDI images and "Raw Write"

[davexnet]

Hello,
when I burn the images in my TEAC cd-w51eb, I have
to select raw write in the advanced options, otherwise the DC
will not boot them up.
My question is, why is this necessary? When the images
were created, obviously quite often by the average user
just making a CDI from his working "backup", he didn't
use RAW READ - then why do I have to use raw write?

My understanding is that when raw write is selected, either
diskjuggler or the actual image will provide some of the sub-code
data, and the burner will write it as is. If raw write is not
specified, only the actual game data is sent, and the burner will
create and use all of it's own subcodes.

This implies the burner is not capable of creating valid subcodes,
but discjuggler is? Am I not understanding this correctly?
Any info appreciated.
Dave