1. Writers: Should novelists write to a particular market? Should they follow the conventional wisdom of knowing where their books will go in the bookstores BEFORE they begin?
2. Here's another bit of conventional wisdom: you should write what you've written so that your audience can understand and stay with you. Readers, what do you think of that?
3. Readers: do you know when you’ve found an “honest” writer? Or honesty in the fiction you’ve read? Can you give us any examples?
4. Everyone: Does honesty in writing even matter?
5. Everyone: What the heck is “honesty in writing,” anyway?
I think writers in the very early stages (discovering voice, exploring subject matter) shouldn't concern themselves too much with where their books will fit in the market. I think honesty in writing is writing about something that affects you firsthand or that elicits a genuine, powerful reaction from you. You may not be able to do this while trying to write to a market.
Novelists who've sold a genre book and are planning another in the same genre should keep in mind the ins and outs of the genre, yes.
Depending on what you're writing, honesty matters to different degrees. Memoirs are expected to be brutally honest, but for fiction it only matters that you start with a seed of honesty to ground the story in some universal human truth. As long as you keep a sense of that center, you can embellish and imagine in any direction the story takes you.