Merge pull request #2243 from dmathieu/comment

Help the next guy with explanations - See bb3b3e306

actionpack/lib/sprockets/assets.rake

@@ -10,6 +10,7 @@ namespace :assets do
     Sprockets::Helpers::RailsHelper
 
     assets = Rails.application.config.assets.precompile
+    # Always perform caching so that asset_path appends the timestamps to file references.
     Rails.application.config.action_controller.perform_caching = true
     Rails.application.assets.precompile(*assets)
   end