I asked this question and received an excellent answer from DavidPostill, for which I am grateful.
However DavidPostill always answers questions by repeating the relevant part of the question in the answer. This might make sense in lengthy and multipart questions such as this, this, and this; but I would imagine it to be completely unnecesary in a short and simple question like mine, or like this and this -- the question shouldn't need repeating in the answer.
What is the community's feeling on this?