I have just been looking at what Nicola Morgan

says is the 'almost perfect' covering letter for the submission of a manuscript to an agent. (Head over to her "Help I need a Publisher" post for yesterday if interested.)
I was surprised at how long it was. Obviously they do things differently in the publishing world. It is a 'sell yourself' sort of pitch that I always feel uncomfortable with. I am not good at saying I am good, especially so good that you should employ me or publish me. If it is good enough then it is obvious. I should not have to say it.
A letter of submission as long as NM's to a government agency of any sort, or your local member of parliament would be - well, ignored. They want a short, short, short letter. It is a different sort of pitch altogether.
Then there are "Letters to the Editor" - usually read by young journalists who sift out the worst. It helps if they know your name. It is more likely to get included on the table at the editorial meeting. You still keep it short - most of the time. You have to be known at the paper in question to get anything more than 100-150 words in. They prefer 50-100 words. Anything else means being someone whose name is in the media often enough to be known - or a serial letter writer like myself. It is another sort of pitch.
In my kittweenhood I participated in a game of cricket against the biggest names in cricket. (Naturally they were being very nice to us mere kittens and allowing us to 'win'. ) At one point in the game I actually managed to throw (I will not say 'bowl') the ball straight enough to hit the wicket while the attention of the biggest name in cricket was momentarily distracted. He bowed out gracefully. I never meant to do what most cricketers could only dream of doing. It was a sheer fluke it hit the wicket. I suspect that getting a novel published is a bit the same. You need to bowl in under the radar, when the defences are down.
Getting a much longer letter into the papers not quite the same. It is a different sort of achievement. It suggests that they think you really do have something serious to say. What is even better is to get some feedback. This can, of course, be howls of rage and expressions of disgust and contempt from the population at large. It is the risk the letter writer takes. Pitched carefully there is an opportunity to make people think. It takes practice. It is a responsibility. It can have unintended consequences - hopefully, good consequences. It is not the same as pitching to a publisher of books, or their agents.
Perhaps I will manage another almost perfect pitch one day. Part of it will be practice. Most of it will be accident. I still have to find the courage to pitch to someone who can bat for me.