NOT.1:4.6 - Retain the decision at the scale needed for the next construction

State the operation to support, the distinction it needs, how a candidate carries it and the burden or unresolved choice that remains. A short explanation beside the candidate can suffice. Keep the contrasting cases when they will help construct, teach or revise the rule; no separate requirements document is necessary for an ordinary small use.

Stop when the next notation construction or choice is clear enough to undertake. Detailed expression formation, interpretation and transformation can then be developed where needed. Do not reopen every design choice merely because a new example is available; reopen the choice whose supported operation or conditions changed.