Notwithstanding any other provision of law, whenever the Secretary of Agriculture determines that additional legislative authority is necessary to develop new agricultural programs involving supply adjustments or marketing regulations through marketing orders, marketing quotas, or price support programs with respect to any agricultural commodity, or to make substantial revisions in any existing agricultural legislation or programs, he may consult and advise with farmers, farm organizations, and appropriate commodity organizations, if any, for the commodity involved, to review the problems involved, the need for new legislation, and the provisions which should be included in any such proposed legislation.