I'm using the User Agent Groups feature of W3 Total Cache to present a mobile template to users of a certain set of devices - the automatic switching works just fine.
However, I'd also like to be able to provide a "View full site" and "View mobile site" link to visitors, so they can switch between mobile and desktop views as they wish.
I've tried using the 'template' filter hook, adding a filter that runs with lower priority (i.e. later) than W3 Total Cache's, but if the user's choice doesn't match what W3TC wants to show them, then WordPress appears to try and load both themes, which is obviously not a good thing when both might have identically named functions.
Is there a way to safely and cleanly override W3TC's theme choice, or am I going to have to use another method of switching themes this way?