BLESS your Sass files through compass (BLESS will need to be installed through Node first).

config.rb

# Just in case the file goes over the IE limit,
# split the file into multiple.
on_stylesheet_saved do |filename|
  begin
    result = system('blessc',filename,'-f')
    if not result
      Kernel.exit(false)
    else
      puts "Blessed the file, so it will work in older versions of IE."
    end
  rescue Exception => e
    puts "Please install bless.\nsudo npm install -g bless"
    Kernel.exit(false)
  end
end

👍