Whe I saw this question, my expectation was that most people would get it right - after all, there have already been several questions that basicallly tested the same concept. The word "superfluous" already started to form in my head.

After answering, I was shocked to see a score of only 39% (at that time) correct answers. Almost half the people (48%, to be precise) apparently STILL think that data in a table is always physically ordered by the clustering key. So I have to apologize for the critique I (fortunately) never uttered - this question is far from superfluous, it is still very relevant and will probably have to be repeated yet more often.

It's too bad that the author did not include a reference. For instance, the books online description of clustered indexes at http://msdn.microsoft.com/en-us/library/ms177443.aspx (found after a one-minute search), that contains a nice graphic of a clustered index - though it unfortunately never mentions that the actual locations of the depicted pages on disk can be completely random.

But apart from this missing reference, the question is good. Thanks! 😉