Every argument on radians you presented applies equally well to Tau as Pi.<p>My original point is that IMHO,  mainstream radian educational materials should NOT use the lesser-known and niche &#x27;tau&#x27; in lieu of the globally understood &#x27;pi&#x27; (other than a possible footnote or sidebar). Ie - it can cause more confusion to the student, especially when connecting it back to the greater scope of their studies.