I cannot imagine under any circumstance when I would ever  want to use any office function online.  How does one make sure it is off and stays off and never comes back on

Hi Paul,

Thanks for your post.

I'm not sure whether I've understood your concern correctly or not. Are you concerning that the Office Online service will outage in some cases?

Please be assured that Microsoft appreciate the serious responsibility we have as a service provider to you. Even if the service interruption occurs, we will make sure to solve the problem in the first time.

Also, as always, if you are experiencing any service issues, you can contact our customer support team: http://support2.microsoft.com/gp/customer-service-phone-numbers/en-us

Regards,

Ethan Hua
TechNet Community Support

What makes you think it's on in the first place?

You can clear the check box next to "Allow Office to connect to the Internet" at File tab | Options | Trust Center | Trust Center Settings | Privacy Options. Note that this also means that you won't have access to online help.

A less drastic approach is to select "Save to Computer by default" at File tab | Options | Save. You should also sign out from your Office account, via File tab | Account.