I'd be far too worried about being incorrect when describing a derivation. I also studied physics not maths but the same goes for physics articles.

I think post-docs are probably better suited for accurate explanations but at the same time they are (at least, fairly often) not as good at explaining a concept using a simpler framework.

The other problem is that because different editors write maths articles, related concepts can use fairly different terminology or concepts with similar derivations use different derivations leading to possible confusion about how concepts are related.