Originally Posted by m3l7d0wN
I think sd rescue needs at least p1 partition
I'll second that - at least in the status quo and judging from the logic as far as I understand it: On the firmware as it is, there seems to be a basic bootstrap chaining to the actual bootloader(s) on the file system, to boot normal or into recovery.
So it should be - in principle - possible to change the firmware (if it can be flashed? - not talking about manipulating mmcblk2 in rooting and so on) to look for the bootloader on the SD, mmcblk0. But if - in the scenario of uboot - the internal memory is already blank, there probably would be no way to flash a new firmware - a hen-and-egg problem.
But: the firmware may very well already be clever enough to look somewhere else if it does not find something on mmcblk2 - we just don't know and probably the only way to find out would be the experiment suggested by uboot (or looking into the firmware...).
Finally, it may also be that you could flash the firmware over the usb/serial-interface without recovery running - I think many embedded devices have that possibility, but do we know about the T1?
My 2 Rappen without too much insight, so ignore if