Enable OpenInClient feature for Onedrives

[Matt McNabb]

I found this guide that details how to enable the OpenInClient feature for a Sharepoint Online site collection and have a few questions. 

Can this be selectively enabled on certain personal sites?

Will this do what I expect, and force Office docs to open in a desktop client?

What will happen if the user does not have Office installed? Will it fall back to using Office Online?

Thanks!

[#2]

Whoops, just realized I posted this in the admin center space. Can I move this?