I'm not sure what is meant by "hiding the mirrors" . . . the mirrors are supposed to be understood as mirrors. Hiding that fact was ever the idea. Maybe they mean some mirror on the other side of the themed mirrors used to achieve the effect?
On another note, hasn't that wall always been lit? Unless there's some major new development in lighting I guess it's possible that they simply never noticed it before . . . who knows. Photos or video would help, if they have any.