While I agree with the idea that the CIA abuses power, techniques that enable effective communication are a HUGE advantage. Knowing how to write in a way that other people can actually understand (and take action on) is absolutely advantageous (as is any other technology that reduces miscommunication). Of course at this point in time you can take a course like Little Red Schoolhouse and come away with many, many practical actions you can take to improve the clarity of your written communication, so probably in effect is has already been declassified.