Some of you have heard me rambling on about how we actually read and see type (and if you haven't consider yourself lucky).
Here's a little primer which explains a lot of it and includes some good tips and rules of thumb. The page I linked to from this (on the same site) has some interesting manuscript layout tips which aren't "universal" so I'll stay away from that.
But, look there. See, I'm not so crazy as you thought. Also, this is definitely based on US preferences. It changes a little from country to country (like our preference to see type with serifs in the US, but in Europe they prefer sans-serifs).
A shout out to Astrid who sent me the original link.