Eh. Obviously a mathematician. Because for us engineers, math is simply the tool and we do not get wrapped around the axle about how we define arbitrary variable names. Rather, we just use the tool. The use of a letter to represent important constants is just that, a placeholder. What is important is the underlying concept behind it, in other words WHEN and WHY you use one tool for one job and other tools for other jobs. That is why it is typically the mathematicians who get wrapped around the axle about this, hence the comment in the video about how "math should be elegant." Yeah, if you are about math for math's sake. If you are about math as a tool to solve problems, it does not need to be elegant, just utilitarian.
But nice find, Einstein!
RMT