Conservatism can affirm both gradual change and drastic change

Reading an recent article about Carlyle in Chronicles caused me to realize that Conservatism can affirm both gradual change and drastic change. The position of Burke and Kirk of accepting only gradual change as ethical is of course the preferred default method of change, but when you look at real history drastic change happens a lot and even seems sometimes necessary and realistic to correct a worn out and corrupt world---and it happens in biological evolution too. This realization doesn't change my preference for gradual change, especially since revolutions often make things worse, but it solves that nagging feeling I have always had with conservatism accepting only gradual change.