Layerblending Materials based on distance to increase performance?

The title says it all really.

Does lerping / layerblending materials based on distance increase performance?

I have created an auto terrain material which is slope and height based and also includes tessellation and on small scenes it works beautifully but if I go and make a big world terrain piece my FPS drops from a solid 60 to about 12 fps and I am not really sure what I can do other than optimise the material or find another solution!

Either subdivide the world terrain into pieces and have them load in and out, increase the terrains LOD factor which looks aweful or don’t use my new material… :confused: