By giving it a quick read I saw that the have n data points where a polynomial of n-1 degrees provides a useful fit in the sense of this blog post.

Every field has its own language to speak. And shouting into the field from "outside" that they should change is not polite.

E.g * if you redefine c = n-1 the connection between number of points and dimension is lost. * c ist very often used as a constant Skalar. E.g as the speed of light. Using it as a dimension of a problem is quite unintuitive.