Acceptance also required that the holders of debt be able legally to enforce an unconditional right to payment; it required that the notes (as well as drafts) be negotiable instruments.
What makes it a system is that it employs cash-substitutes; traditional payment systems are negotiable instruments such as drafts (e.g., checks) and documentary credits such as letter of credits.
The court rejects this argument, that no obligation can be found to be a cash equivalent unless there is a negotiable instrument, as too unrealistic and formalistic.