Our only measure of data is what we've used for testing our velocity. We've found that velocity increases when 2 or more are working from home on any given day. When I know a particular feature is going to require a lot of concentration, I don't think twice about popping into our #standup channel around 6am and saying: "wfh today".

Now, when it comes to bugs, I'll admit, tossing it up on big screens and inviting a few co-workers is just awesome. It's like playing solitaire with someone watching... they always see things that you would not.