> Here’s a letter Watney writes for Johanssen in case he dies. Johanssen is the “hot chick” on the mission. He also tries to tell her how to dress and how to act. Perhaps Watney also wanted her to smile more.

> > Johanssen: Your poster outsold the rest of ours combined. You’re a hot chick who went to Mars. You’re on dorm-room walls all over the world. Looking like that, why are you such a nerd? And you are, you know. A serious nerd. I had to do some computer shit to get Pathfinder talking to the rover and oh my god. And I had NASA telling me what to do every step of the way. You should try to be more cool. Wear dark glasses and a leather jacket. Carry a switchblade. Aspire to a level of coolness known only as…“Botanist Cool.” Did you know Commander Lewis had a chat with us men? If anyone hit on you, we’d be off the mission. […]

I haven't read the book but isn't the "dark glasses and leather jacket" bit here Watney paraphrasing what he was told by NASA to do? Not Watney telling Johanssen what to do?