There will be some tweaking due to the fact that the new shaders use the lightmap generated during the build to achieve some of these effects. copied all the shaders into a different folder and open them with notepad and look at some of the things you can change. (Tweeks) I try to modify the wesser shader in mental mill the program it was compiled in and made a total mess of the shader.
Start comparing the old shaders to the new ones so you can see what they due.
Dark shader looks like a very nice program to adjust your shaders in, as bond1 show in other threads. But there are some things that have to be retrieved by the in game camera to render properly. Thats where the difficult part lies. Even slapping some shader together in a shader making program, and making it work it FPSC, are to different animals. (FX composer makes great shaders, But they are a bear to get into FPSC).
So in answer to your question, It does, But it does not do magic for you. You have to run and understand it just like any other tool your use.
Nothing but coffee in my veins