I also thought at the first glance he has something seriously do with matrix calculus, but from the rest of his posts I really doubt it is so.
Transforming large meshes? On a CPU? Could you give an example? I really think that should be done on a GPU.
This is mobile, and even though the mobile GPUs are quite powerful, they still are far from desktop systems, and sometimes you want to use the GPU cycles for shading, and offload some vertex processing work to the CPU. In those cases it feels foolish to not use the entire CPU, and ignore the excellent SIMD instructions. You quite easily get up to 4x the processing performance by using NEON.
Also, there is more then the graphics pipeline that can use some matrix calculations, and with limited resources, you don't want to needlessly waste any