Not to be snarky, but the fact that it has become straightforward to build Sinatra as an extension to Rails is one of the things I don't like about Rails.
The article just seems to be putting Rails 3 design improvements to the test. Personally, I am pretty impressed at how easy it is to swap out Routes/ActionController::Base if you need something leaner or just a completely different approach to routing requests. Remember when we were all banging our heads against a wall with Struts? What's not to like?
You're right, of course, I just think it's ironic that he'd use Sinatra as an example, because Sinatra is what people run to when they get freaked out by Rails complexity.
Or they don't need a framework as robust as Rails for a simple application
What's ironic is that the post is meant to appeal to those who always have another "one of the things I don't like about Rails." So your pithy-dig response is just perfect.
Yehuda is nicely filling the void left by Jamis Buck after he stopped blogging about Ruby/Rails.