I don't remember noticing during my (mostly pure) maths degree that most of the time I was using pi that I was actually using 2 * pi. So there must have been a

I don't remember noticing during my (mostly pure) maths degree that most of the time I was using pi that I was actually using 2 * pi. So there must have been a lot of problems where I would have been writing tau/2 using the proposed system, which I find less nice than simply writing pi. If it's a choice between splitting my writing between [pi and 2 * pi] and [tau and tau/2] I'd prefer the former, multiplication is nicer to look at than division (in my opinion).