Has anyone ever really understood how it happens that code produced with qhasm is so fast? I understand code unrolling, but DJB mostly gets speed because he und

Has anyone ever really understood how it happens that code produced with qhasm is so fast? I understand code unrolling, but DJB mostly gets speed because he understands the sequence of instructions in an algorithm well. As far as I remember you had to have a machine architecture spec for this tool. So I wonder if it's a more optimized register allocator?