Technically correct, but it ignores one little detail: Calling ->new is the normal, default way to create an object. Calling bless directly is not.

There's quite a difference between expecting people to not instantiate an object in a way which 99% of classes consider to be an unsupported backdoor "here be dragons" approach (bless) and expecting them to not instantiate it in a way which 99% of classes consider to be the standard way to do it (calling the ->new method).