Nexus 7 2013 - adb shell cat /proc/cmdline

*The highlighted section is what matters here. I think the the device has nothing on the emmc, so its loading the recovery into RAM and calling for the console configuration (tty COM port), so we get console=ttyHSL0,115200,n8 added to the commandline.

Bricked

E:\android_development\sdk\platform-tools>adb shell cat /proc/cmdline
console=ttyHSL0,115200,n8 androidboot.hardware=flo user_debug=31 msm_rtb.filter=
0x3F ehci-hcd.park=3 androidboot.emmc=true androidboot.serialno=049973d5 bootrea
son=PowerKey fuse_info=Y ddr_vendor=hynix androidboot.baseband=apq asustek.hw_re
v=rev_e androidboot.bootloader=FLO-04.04

Working

E:\android_development\sdk\platform-tools>adb shell cat /proc/cmdline
androidboot.hardware=flo user_debug=31 msm_rtb.filter=0x3F ehci-hcd.park=3 andro
idboot.emmc=true androidboot.serialno=08e6d154 bootreason=Reboot fuse_info=Y ddr
_vendor=hynix androidboot.baseband=apq asustek.hw_rev=rev_e androidboot.bootload
er=FLO-03.15