Clean up styles

I've begun the work of making the implementation of style methods more uniform and correct, but this got to be so big that I decided to stop half-way.

This PR will represent "cleaning up" `arc` - `list_box` (using the list in #711).

I'll make lots of inline comments on what I considered "cleaning" and I'm eager to hear feedback.
Oh, huh . . . when we were talking about this before I was looking at the code snippet here in the browser, now that I'm looking at it in my editor I'm noticing for the first time what you meant by your first comment about dropping the method argument!

I didn't notice before that the method argument is called style too! 

In this case wouldn't that mean it wasn't calling the style method anyway?

Either way, I'll keep the change to `@style` and drop the first argument.