[tptacek]

He's arguing that users should be able to elevate their privileges by supplying root's credentials and then create a simple directory without having to reboot.

I more agree with you than with him, but his argument seems pretty straightforward.

[quesera]

Well, if you unwind far enough, I think the original discussion was about why Homebrew has trouble using /usr/local. Where "using" means "owning, adding git repos to, changing permissions on, etc".

OSX suggests /usr/local as a good location to install software, but insists that the directory itself be owned by root, and protects the parent directory /usr under SIP.

My assertion is that Homebrew is using /usr/local incorrectly (and in contravention to all expectation), and that blaming Apple for the problems thereby created is inappropriate.

I also think SIP is a good thing.