Top Hotels Getting a better rate when you check in

Someone I met once told me that they always ask if they have actually reserved the best rate for their room whenever they check in. And quite often the person who checks him in will tell him that they can do better on the rate and makes the adjustment right then and there. He said it never hurts to ask, and occasionally it works.

I'm curious if anyone else here has ever done this at a high-end luxury hotel, and if it's actually worked.