http://techreport.com/news/31328/microsoft-releases-open-source-directx-shader-compiler

How helpful is this to LFS currently? Will it work on DX9?

https://github.com/Microsoft/DirectXShaderCompiler

GitHub link for those that want it.

I don't think it will work for DX9, because it needs a specific driver support and it's primarily made for more recent hardware and software (DX12 and Shader Model 6). And even if it does work with DX9, it won't help LFS in any way.

I actually don't get how tools for engine development could suddenly make a game better looking. In every case it need work to take advantage of it, and in this case, there is zero use to go DX12 and SM 6.0, and will make 90% of the userbase not able to play LFS anymore, while providing no graphical improvement by itself.