[marshallward]

I don't disagree, but where are those techniques presented in the article? It seems like she exploits the particular shape of her matrix to align better with cache. No BLAS library is going to figure that out.

I am not trying to say that a simple 50+ year old matrix solver is somehow competitive with existing BLAS libraries. But I disagreed with its portrayal in the article, which associated the block with NumPy performance. Give that to a 2024 Fortran compiler, and it's going to get enough right to produce reasonable bytecode.