Bill de hÓra: let’s take the ws guys seriously now they’re recanting. Sigh.
Any day now, they might even discover ETags.
That question wasn’t chosen as it identifies a random HTTP header that happens to have a very practical benefit. That question was chosen as it identifies an HTTP header than happens to have a practical benefit AND requires one to pierce layers upon layers of “value-add” infrastructure to implement correctly.
Related: see Patrick Mueller’s exploration of twitter.