"But concise is not always precise, and without precision, concision is just vague at best, and misleading at worst. Several years ago, a student wanted to contest the scoring of one of his test answers in my introductory psychology course. The test question was something to the effect of “What is the primary advantage of an experimental study over a correlational study?” and an example sufficient answer would have been, “Causal conclusions may be drawn from an experiment, but not from a correlational study.”

The student’s answer was, “In an experiment, you actually test something” (the word ‘test’ was underlined twice). When he questioned why his answer earned no points, I explained that it failed to distinguish the two study types at all, as both correlational and experimental studies “test something” (i.e., in introductory terms, a relationship between variables and cause-and-effect, respectively). He looked at me earnestly and rebutted, “But you said some of the questions could be answered in one sentence, and I underlined ‘test’ twice.”

After a moment of silence (to contain my disbelief at his statement), I asked him what it would have meant if he had only underlined “test” once, or not at all, and how was I to know those distinctions in meaning. He had no answer."

--"Precision First", L. Kimberly Epting