HCD.28:4.1 - Bound the offer by work and meaningful entry differences

Describe a family of later tasks, the contribution a learner must supply, the help that may remain in later work, and the errors that defeat the result. State the audience hypothesis and the observations that would make entry plausible. “Engineers” or “beginners” is too broad when some can calculate correctly but cannot select a model.

Separate what the offer must teach from what entrants may already know and what a reference, tool or specialist may legitimately supply. Do not convert every useful contribution into a prerequisite to be memorized. Conversely, a tool that supplies the very choice to be learned changes the learning task.

Construct branches only for differences that change an action. An entrant who confuses units may need a short preparation task before joining model comparison; an entrant who already selects models may need a different challenge or no such module. Specify a representative entry action, the result selecting the branch and where that branch rejoins. Uncertain preparation may justify an early diagnostic attempt rather than a lengthy prerequisite course.

Keep audience assumptions conditional until learners arrive. Return compatible product variants, requirements and limits to HCD.2 for a known person’s comparison. HCD.2 adds that person’s starting performance, later work, participation, access and protected contributions; an average audience profile supplies none of those personal facts.