Here is the *Gold allowance:

As a Gold Status holder you can choose not to travel light. We allow an additional 20 kg (44 pounds) where the weight concept applies, or one additional piece of luggage where the piece concept applies.

Individual carriers such as UA choose to give their elites more, but that's got nothing to do with *A.

All of this is programmed into US' software so the CSR's which whom you are dealing know exactly what they are doing.