Because Rubyists knows the value of everything, but the cost of nothing.

dci_bench.rb

require 'benchmark'
require 'delegate'

class Direct
  def method
    'direct'
  end

  def base
    'base'
  end
end

module Role
  def method
    'role'
  end
end

class Delegated < SimpleDelegator
  def method
    'delegator'
  end
end

puts 'Injected method hit'

def heaps &block
  100_000.times &block
end

Benchmark.bmbm do |x|
  x.report('direct') { heaps { Direct.new.method } }
  x.report('role') do
    heaps do
      d = Direct.new
      d.extend Role
      d.method
    end
  end
  x.report('delegator') do
    heaps do
      d = Delegated.new Direct.new
      d.method
    end
  end
end

puts
puts 'Base method hit'

Benchmark.bmbm do |x|
  x.report('direct') { heaps { Direct.new.base } }
  x.report('role') do
    heaps do
      d = Direct.new
      d.extend Role
      d.base
    end
  end
  x.report('delegator') do
    heaps do
      d = Delegated.new Direct.new
      d.base
    end
  end
end