This is such a myth.
I have TWRP 18.104.22.168 as "permanent" recovery and I am able to flash any ROM from any ROM.
I just flashed this KK ROM from MIUI ROM which is, as we know, JB ROM.
So please let's stop this misleading nonsense that you have to be on KK ROM in order to flash another KK ROM. Or that you have to be on JB ROM to be able to flash another JB ROM.
Isn't the real issue only about installing TWRP?
Once you install TWRP you can flash any ROM for your device regardless of what ROM you are currently on.
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