That's kind of an odd comparison, using unfused C code compared to fused Haskell code. Their point seems to focus on stream fusion's advantages and possibly tha

That's kind of an odd comparison, using unfused C code compared to fused Haskell code. Their point seems to focus on stream fusion's advantages and possibly that optimizing C takes more effort. To quote the paper: "Clearly “properly”-written C++ can outperform Haskell. The challenge is in figuring out what “proper” means."