I once worked with a brilliant engineer. He was from Hong Kong. He struggled to express his ideas in English. We tended to let him show us in code instead.
Sometimes this worked. Sometimes it really, really didn't. It also meant we had a very difficult time discussing larger architectural questions with him or giving him useful feedback on his code.
Well that's half cultural, I meant in a context of shared native tongue. Now international work does create lots of hurdles because you can't translate things above casual smalltalk. I guess that's where maths could help.
Sometimes this worked. Sometimes it really, really didn't. It also meant we had a very difficult time discussing larger architectural questions with him or giving him useful feedback on his code.