SeanC wrote:It's helpful to have a concrete example.
So using the example the complete beginner would have to intuitively know what a black U was.
Well that certainly highlights another problem with text descriptions - ambiguity. You have read the description less carefully than needed (and not even under competition pressure) and are looking for the wrong feature on the map.
The icons for depression and small depression correspond much more intuitively to the map symbols thus making the symbolic description much more useful even to people who understand the meaning of the word depression.
Then we come column C & column G which is actually the more important part of the description since it gives information in addition to what is on the map. Do you find the word "northwestern" easier to interpret than an arrow?
I think we've had all these discussions before. One of the previous points was that control descriptions were codified in the era of black and white printing. Now colour printing is possible control descriptions could at least use the same symbols as the map rather than offering two separate symbols for the same thing.
They are black and white for clarity - purple used to be common (as part of the overprint but now black is specified in the rules). Printing things in different colours would just make them more difficult to read - before even considering colour blindness.