From Math to Music --(Learning the Fretboard)

Dear,

I was reading carefully the article : A Mathematical Approach to Learning The Fret Board.
Very interesting approach...

Just a question : is there a reason why you give specifically the A-note a "0" (zero) value ?
I mean : is it more practical to give the A-note a "0" (zero) value for the remaining theory on scales etc...
Is it not more practical (if f.ex. learning the Major scale, Modes, etc...) to have the C-note as a "0" (zero) value ?

BR

Dany