When the questioned agency action does not jeopardize substantive rights or have a "substantial impact" on the purportedly regulated parties, or "create substantive effects upon the rights of the parties not involved in the proceedings," then lack of compliance with the prior notice and comment requirements of the APA is not fatal.

Under the FAA, any doubts regarding arbitrability should be resolved in favor of coverage under the Agreement unless it "can be said with positive assurance that the arbitration clause is not susceptible of interpretation that covers the asserted dispute."

The court held that, although the individuals here were on layoff status when the alleged misrepresentations were made to them, "an employee in a layoff status is still an employee for purposes of... a collective bargaining agreement."

A rule creating a rebuttable presumption that abandonment of branch railroad lines would be permitted if less than 34 carloads per mile were carried was held procedural.

To solve this problem we need not go exhaustively into all the general criteria for distinguishing one type from another.

—for instance, but it would be easy to write an equally defensible opinion characterizing such a rule as substantive.