Thinking on a further refactoring on a nice blog post regarding flog, using a Session Model came to mind to assist with the responsibilities. POST: http://cored.github.io/blog/2014/02/19/my-gpa-at-code-climate-is-3-dot-59-a-refactoring-story

last_tracks.rb

class LastTracks
  attr_accessor :session, :list

  def initialize(session)
    @session = session
    @list = []
    yield(self)
  end

  def blacklist(url)
    list << url
  end

  def previous_url=(came_from)
    return unless valid_origin(came_from)
    session[:previous_url] = came_from
  end

  private

  def valid_origin(came_from)
    !list.any? { |no_return| no_return =~ came_from }
  end
end

# APPLICATION CONTROLLER

before_filter :record_tracks

def tracks
  @tracks ||= LastTracks.new(session) do |tracks|
    tracks.blacklist some_path
    tracks.blacklist another_path
    tracks.blacklist one_more_path
  end
end
helper_method :tracks

def record_tracks
  return if request.xhr?
  tracks.previous_url = request.fullpath
end

@cored Yeah, first got the hang of using Session Models from a railscast yonks ago: http://railscasts.com/episodes/119-session-based-model it's served me well since then.