[Plugin: WordPress SEO by Yoast] programmatically remove robots meta

WordPress version: 3.4.1
WordPress SEO version: 1.2.5

I’d like to programmatically override the robots meta output, so on my staging server, no matter what is set with the SEO plugin, I can have noindex,nofollow (for obvious reasons).

However, it seems that the robots function is called by the head function, which is hooked – so I have to remove ALL of the head function, or nothing. And there’s no filter applied before output inside robots.

I do have a mechanism for applying a server-level password to the staging server, but I want to know that there’s never “index” set in the meta there.

http://ww.wp.xz.cn/extend/plugins/wordpress-seo/