Yes, you're correct. I used a rotten example. Here's a clearer example. A corporate customer is assigned to a company, which has an office which has a manager.

Later on, we realize that this is a bad class heirarchy and the customer should belong to an office and the company is superflous to this, but we've hardcoded a chain of method calls and this makes life difficult. What if we had done this:

  sub Customer::manager {
      my $self = shift;
      return $self->{delegates}{company}->manager;
  }

  sub Company::manager {
      my $self = shift;
      return $self->{delegates}{office}->manager;
  }

  sub Office::manager {
      my $self = shift;
      return $self->{delegates}{manager};
  }
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Now the fix is easy, when we want to drop the Company class reference in the Customer object.

  sub Customer::manager {
      my $self = shift;
      # return $self->{delegates}{company}->manager
      return $self->{delegates}{office}->manager;
  }
[download]