So I'm giving this one a whirl and followed all the instructions in the OP. Rebooted and set up wifi and my gmail account. It started complaining about SuperSU binary needing updating. I tried "Normal" way and after a couple minutes it said it failed and to reboot. So I rebooted and my Samsung bootscreen came up with a lock icon and says "Custom" Did this trip KNOX? I'm on an AT&T SM-G900A.
EDIT - Whew! Sorry, I panicked there for a moment. So I rebooted into Download mode and KNOX is set to 0x0 and binary still says Samsung Official. So is that just the custom ROM counter I'm seeing that's causing the new bootscreen (before the VISIX dragon)?