Send in the Clones

[utu]

Klaus2008's idea is to make a new bootable USB, including providing persisent storage,
exactly the same way as the first was made. Presumably from a CD. The only difference
between the two USBs should be the persistent images. You then cut-and-paste with
the USB's unmounted. You erase the clone's new knoppix-data.img file and replace it
with a copy of the knoppix-data.img from the original USB. You can even do the cut-
and paste in Windows, as I did.

[mecho]

One idea - not quite in sync with your discussion, but worth mentioning. Since Utu uses Windows - there is a tool called USB Image Tool. Its available for free from http://www.alexpage.de/usb-image-tool/download/
It makes image of the entire USB including boot sectors and restores it on demand. I use it to back up my Knoppix under Windows. It has an option to compress the image for less space. What I know is, it works well with SD cards too
It can be used to transfer the entire image to another SD card