Thank you for a detailed explanation. How can I opt out from this club?
Last time I've bricked my KT your USB/tar/RUNME.sh method worked perfectly. But this time I never get the possibility to access USB drive. After a restart I can see the drive but not read/write, not even list contents of it. After cca. 30 seconds the drive disappears and KT reboots. This goes on and on without stop. I was only able to stop this loop by booting into USB download mode. But apparently the device was still on because today my battery was depleted. Once I charge it a bit I'll try it again.
EDIT: No luck with USB - I either get "The system cannot find the path specified." when drive is not mounted or "The device is not ready." when it is mounted.