what does the boot only iso of knoppix do ?

Hey folks
I just saw some new files in the knoppix release/download area which are much much smaller and was curious does anyone know what they are useful for ?
For example if you click on the link
http://mirrors.kernel.org/knoppix-dvd/

you will see
KNOPPIX_V7.0.4bootonly-2012-08-20-EN.iso which is just 11M.
going by the name of the file i would have to speculate that it is where in u can use this to boot either dvd or cd whatever you have in the knoppix_dir folder.
but not sure.
has anyone tried ?

If your BIOS is unable to boot from USB, you can use the boot-only CD to proceed with a flash disk installation on an USB stick.