Since the firmware has been updated to 30O, this cannot be done. I used the 'boot recovery' method while on 25R, but for some reason (security?) they have blocked that exploit, hence the question at hand.
I had even tried this method I found in a Nexus forum:
Here's some instructions I compiled for doing useful things with your Nexus. Also includes instruction to root nexus 4 without installing a custom recovery. Basically, you save the customrecovery.zip file then fastboot boot into it (NOT install, and notice you have to type the full command specified below, not just "fastboot boot customrecovery.img") and then install using the custom recovery, install SuperSU.zip for unrooting:
1) Install all STOCK files:
./fastboot flash bootloader bootloader-XXX.img ./fastboot reboot-bootloader ./fastboot flash radio radio-XXX-XXX.img ./fastboot reboot-bootloader ./fastboot -w update image-XXX-XXX.zip ./fastboot oem unlock (to unlock bootloader)
2) If you want to keep stock recovery, fast boot BOOT into custom recovery and install SuperSu.zip: 3) Install SuperSu.zip file (to root)
./fastboot -c "lge.kcal=0|0|0|x" boot customrecovery.img
there used to be a 'fastboot boot recovery recovery.img' command, but Google removed it in 4.3, so now to simply boot into your custom recovery you can type 'fastboot -c "lge.kcal=0|0|0|x" boot customrecovery.img' instead and it'll do the same thing as the 'fastboot boot' command. Meaning it will revert to your stock recovery once you reboot. So boot into custom recovery, flash superuser (Koush or Chainfire's) and reboot. done.
It didn't work but maybe another code for our device is needed?
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