This has nothing to do with the psychological over-diagnosis of ADD. It has to do with not saying no to your children and screwing up their character. It's labeled as Discipline Deficit Disorder as a tongue and cheek poke to those who need to put everything in tidy little diagnostic boxes. As in "I'm sorry, I can't discipline my children because I have DDD." Or "My children have really bad behavior because they are suffering from DDD because of me."
Back up and try reading it again with that in mind and see if it doesn't change the perspective a bit.
Interesting approach. Of course, I could take that "light hearted" approach with everything. But that's exactly how ADD was introduced into psychiatric nomenclature several years ago - by light-hearted jokes with little labels attached. You'd be surprised how these things take off once the pharmaceutical companies get hold of them. How about "Library Misbehavior Disorder"?