Yesterday I started to reverse engineer a viz by James Smith as a learning exercise, and decided to focus on learning how to drill down to more detail by using tool tips.
From James Smith's viz, I learned that I could put a reference to another sheet in the tool tip to pull in maps or graphs. As I played with it, however, I learned that one small space in the tool tip dialog box adds a lot of white space around whatever I'm pulling in to the tool tip.
Anyway, I decided that I wanted to use this new-found knowledge to drill down from state to county in my Premature Death by State viz. The first problem I encountered was the state and county color scales didn't line up. I corrected this by manually setting the start, end and middle for the color scale.
The next problem I encountered was that the states were tiny in the tool tip. I did a search and found Andy Cotgreave's tip about making sure the map being shown in the tool tip is not fixed on it's sheet - there should be no little "X" next to the thumb tack in the upper left.