2015-05-09: While I still want to break down ActiveRecord models, I now disagree with the idea of inheriting from Ruby’s stdlib types and think they should always be wrapped. My RailsConf 2015 talk expands on the thinking below (especially about immutability!) and touches on reasons why not to inherit from stdlib.
Yesterday I (belatedly) took my friend Nola Stowe‘s advice and picked up a book she tech-reviewed, The Rails Way by Obie Fernandez. It’s been a great read so far (about 85 pages in), and I just realized that routing is largely about type conversion.