If you are familiar with "sdparted", it is an old G1 script created by XDA member 51dusty.
It made it's way into JF recovery and AmonRa recovery, and everything was fine and dandy, because all phones sdcards were on "/dev/block/mmcblk0". Then, new phones like the DHD started coming out very recently, and their internal memory would be at "/dev/block/mmcblk0" while their SD card would be at "/dev/block/mmcblk1".
So, sdparted would run, and happily continue partitioning "/dev/block/mmcblk0"... which is the internal NAND. Needless to say, this results in a brick.
The fix was to remove the assumption about what the SD card is located, and figure it out intelligently using /etc/fstab, which is guaranteed to be correct