[protoman3000]

I disagree, because with the way of writing it down we have a homomorphism, e.g. transpositions preserve relations between letters, e.g. (A D E) -> (Ab Db Eb), or (G C D) -> (G# C# D#).

Of course, for every rule there are exceptions, e.g. we have things like (F Bb C) -> (F# B C#)