You should tell people to reboot in recovery partition to use its security utility to disable SIP.
boot-args is going to be removed fairly soon from El Cap as you cannot issue anymore nvram changes while SIP is running.
Yes, I'm well aware of that. The thing is that every time I tell someone to boot to recovery partition to disable SIP, another person (does the same thing you just did) has to jump in and tell me "You should tell people to use boot args instead".