e.g. in Python:

    >>> from decimal import Decimal as D
    >>> 2 * D("1.0")
    Decimal('2.0')

    >>> 2 * D("1.000")
    Decimal('2.000')

    >>> D("1.0") == D("1.000")
    True

The Ion value 0.0 has one digit of precision (after the decimal point), while the value 0.00 has two. In the Ion data model, those are two distinct values, and conforming implementations must maintain the distinction.