are there any gotcha's for this refinement scheme?

joy.rb

# Small module intended for enhancing a string object.
module Joy
  def joy
    self + ' Joy!'
  end
end

refined_joy.rb

# setup the Refinement using include
require_relative 'joy'
module RefinedJoy
  refine String do
    include Joy
  end
end

using_refine_joy.rb

require_relative 'refined_joy'
module TestPositive
  using RefinedJoy
  puts "refined? ".joy #> refined? Joy!
end

module TestNegative
  puts "refined? ".joy #>  NoMethodError "undefined method `joy' for "Refined?":String"
end

want_to_monkey_patch.rb

require_relative 'joy'
String.include(Joy)

puts "monkey patched?".joy #> monkey patched? Joy!