With less efficient technique, I refer to using <object>, <script>, <img> tags to prefetch content, which does not have the goodness of link prefetching mentioned in the article your shared. That is what Chrome on Linux was falling back to.
Link Prefetching is the way to go, and that is what Chrome on (Mac/Windows/Chrome OS) is currently using.
The reason why browser detection is needed is because it is not supported everywhere, e.g for instance, according to http://caniuse.com/#feat=link-rel-prefetch Safari does not support it, so StaticLoad.aspx uses the <object>, <script>, <img> technique, but unlike Chrome on Linux, Safari on Mac does not hang.
Again, this was not intentional. The second technique does not hang on Safari on Mac, but it does on Chrome on Linux. We will definitely ensure that more Linux testing is done! Our goal in OneDrive is to build a service that enables as many people as possible to be productive, so if in cases it looks like we are trying to favor our own OS, that is not really our intention.
Thanks! Edgar