That seems horribly arbitrary to me, not to mention inviting another intdiv fiasco (from sanity import division:). If only Counter was committed to only working with integer values from start, it might be acceptable, but since Counter implementation was always careful not to preclude using Counter with nonint values, it wouldn't make sense.

Also, there is an interesting inconsistency then, in the form of

    c = Counter(a=5,b=5).normalize(5)

Presumably c.a and c.b would be equal integers, and their sum equal to 5. That is unfortunately not possible. :-o