Any trustee may, by written instrument delivered to any then acting co-trustee and to the permissible distributees of the trust, relinquish to any extent and upon any terms any or all of the trustee's powers, rights, authorities, or discretions that are or may be tax sensitive in that they cause or may cause adverse tax consequences to the trustee or the trust. Any trustee not relinquishing such a power, right, authority, or discretion and upon whom it is conferred continues to have full power to exercise it.