What is common knowledge in your field, but shocks outsiders? Politicians don’t write their own letters, speeches, articles, policy papers, laws, emails, tweets, and in meetings they only say what you tell them to say, I mean I’m not even sure what they’re for

The pattern of car tyre treads are chosen by the marketing department and not by the technicians. Sexy tyre treads sell.

I always had that impression about ministers. They know bugger all about the department they head, hence why they come out with such rubbish and obfuscate when put under pressure. It's the civil servants who know their stuff and advise them accordingly.

They keep the spotlight off all the other people that would rather not get the attention as they spend time writing all those letters, speeches, articles, policy papers, laws, emails, tweets and coming up with what the politicians should say?

That journalists write quotes and then find people to attribute them to.

Front benchers, or does this go for all MPs?

I'm sure my MP isn't like that at all :)