Your concerns:

If you do not know whether maintenance mode is blocking "everything you want blocked" by 100% (!) -- but at the same time are very concerned about "whether someone like google might still access it". ... then maintenance mode might be a bad choice for blocking your development site in the first place.

Recommendation:

Personally, I recommend simply adding a .htpasswd to your dev sites.

It is simple to automate even inside aegir deployments. It never gets in your way, because your browser and every command-line tool can skip it for you. You can let other people in. It blocks the site in all completeness 100% to google etc.

Your concerns:

If you do not know whether maintenance mode is blocking "everything you want blocked" by 100% (!) -- but at the same time are very concerned about "whether someone like google might still access it". ... then maintenance mode might be a bad choice for blocking your development site in the first place.

Recommendation:

Personally, I recommend simply adding a .htpasswd to your dev sites.

It is simple to automate even inside aegir deployments. It never gets in your way, because your browser and every command-line tool can skip it for you. You can let other people in. It blocks the site in all completeness 100% to google etc.

If you do not know whether maintenance mode is blocking "everything you want blocked" by 100% (!) -- but at the same time are very concerned about "whether someone like google might still access it". ... then maintenance mode might be a bad choice for blocking your development site in the first place.

Personally, I recommend simply adding a .htpasswd to your dev sites.

It is simple to automate even inside aegir deployments. It never gets in your way, because your browser and every command-line tool can skip it for you. You can let other people in. It blocks the site in all completeness 100% to google etc.

Your concerns:

If you do not know whether maintenance mode is blocking "everything you want blocked" by 100% (!) -- but at the same time are very concerned about "whether someone like google might still access it". ... then maintenance mode might be a bad choice for blocking your development site in the first place.

Recommendation:

Personally, I recommend simply adding a .htpasswd to your dev sites.

It is simple to automate even inside aegir deployments. It never gets in your way, because your browser and every command-line tool can skip it for you. You can let other people in. It blocks the site in all completeness 100% to google etc.