My current work in progress is what I call a "research heavy" book. That means, basically, that it's about shit I don't know enough about to just jump in and wing it. It means I get to study a bit, and if I do it right, have some fun learning new and previously unknown things.
One of the pitfalls of research heavy book; however, is the temptation to insert everything you learn about a topic straight into your manuscript. Most will advise against the unrelated information injection. It makes a book clunky, and it can bore the blue bejeezus out of your readers. Particularly if they aren't studying for a doctorate in herbalism, the history of writing devices in western civilization, monkey genetics, or whatever it is that you have discovered and become suddenly, inexplicably obsessed with during your research.
As an author, when the time comes to put words on paper, most of that wicked shit you've discovered has to stay where you found it. Rather, it has to stay out of the story...and out of the story's way.
That being said, I'd like to point out that during the pre-writing phase, all bets are off. In fact, so long as you promise to restrain yourself mightily once you actually start writing, I suggest going absolutely fantastically crazy with the depths of your research.
I have a theory that the more obsessed you get over a topic, the more you really dig in and try to absorb it, the easier it is NOT to cram it down your readers' throats.
Because if you know it well enough, you won't have to.
When you first learn something, it's new and shiny. It's also on the surface of your little pool of knowledge, floating there where you can accidentally step in it. Once you have integrated the information, though, it goes deeper. It becomes fused with the big ocean labeled "all the shit I know." After that happens, it's a lot less conscious. It's not an effort to retrieve it, and so, it flows way more naturally.
That's my theory anyway. More significantly, I enjoy going a little crazy over a topic. I like the research stage and I've been known to get a little obsessive from time to time. If I'm writing about the 1950's (and I am) it seems logical to spend a few weeks listening to the music, watching the newsreels, wearing the clothes. I'm not suggesting we take up method acting for every book, but it seems like actually wearing a girdle would make an author more likely to write about how and where they tend to pinch than about how they're constructed.
And as far as story goes, I think the the pinching wins.
I'm also interested in how other folks research. I'm even more curious about any crazy, possibly over done, things other authors have tried when channeling their inner method actor.
Because I know I can't be the only one who tried on the girdle.