Completely agreed, the title is a red herring and serves to dissuade people from giving DCI a try. "It's too slow" is not an argument against DCI, it's an argument for fixing a slow implementation of #extend or using a different method.
s = "foo"
d = SimpleDelegator.new s
s2 = d << "bar"
s2.object_id == s # true
# delegate.rb L117
#
# Returns true if two objects are considered of equal value.
#
def ==(obj)
return true if obj.equal?(self)
self.__getobj__ == obj
end