(a) An issuer may not issue refunding bonds if the aggregate amount of payments to be made under the refunding bonds exceeds the aggregate amount of payments that would have been made under the terms of the obligations being refunded unless:
(1) the governing body of the issuer, in the proceedings authorizing the issuance of the refunding bonds, finds that the issuance is in the best interests of the issuer; and
(2) the maximum amount by which the aggregate amount of payments to be made under the refunding bonds exceeds the aggregate amount of payments that would have been made under the terms of the obligations being refunded is specified in the proceedings.
(b) An issuer is not required to comply with Subsection (a)(2) if the governing body of the issuer determines and states in the proceedings authorizing the issuance of the refunding bonds that the manner in which the refunding is being executed does not make it practicable to make the determination required by that subsection.