Originally Posted by
jamawani
I suspect it was a beta test that was supposed to be in beta mode,
but somehow it went live by mistake.
I never saw it, but also didn't try too hard to find it.
Not sure in this situation, but one technique that also gets done is A-B testing on a live site. You subject some subset of the population (A) to your new change and then compare the response to the other population without the change (B). So perhaps it was there by mistake but there are also scenarios where feature trials are intentional.