Environment load time increases drastically when many routes are added

Here's rake routes of gitorious.org's Rails 3 rewrite. http://ditrw.com/_dump/gitorious_rake_routes.txt (also attached)

rake environment churns for about 20-25 seconds before it exits. If I remove all the routes, it takes about 3-4 seconds.

Here's routes.rb and friends at the time of the rake routes output above: http://gist.github.com/423134

I added a puts at the bottom of routes.rb. That appeared after 5 or so seconds, so it seems that it's not the execution of routes.rb that takes so long, but rather whatever Rails does with post processing them as the environment loads.