I'd be OK with this if it were for a limited time - i.e. run it for a month, with a very clear banner at the top indicating what's happening. Make a blog post a

I'd be OK with this if it were for a limited time - i.e. run it for a month, with a very clear banner at the top indicating what's happening. Make a blog post afterwards with the data (or better yet, have a separate page showing persistent data), shut down the feature after that.