...Mr. Bennet knows himself. I understand being able to say, he's willing to take the blame. It's certainly a step in the right direction. The question then becomes, once you admit to a fault/s, what are you planning to do about it? We're watching Elizabeth struggle with the admission of her faults and working on changing that. Darcy had stepped up to the plate and admitted his lack of responsibility in the Wickham debacle and has tried to rectify it as much as possible. I think this is what we are meant to see as the correct method of dealing with admissions of blame.

If you smoke and admit it's a fault but don't plan on stopping as long as you aren't hurting someone else, then that's one thing. Mr. Bennet knows he will continue his "doing nothing" at the possible detriment of his family. Knowing and admitting it makes it worse (imo) to continue on the same path when you know you will never have to suffer yourself in the same way your family might. It's like a twentieth century equivalent of something I've seen: families become homeless, furniture and belongings sitting on the curb, mother and kids having to find someone to take them in and a father, who knows where, who could care less---he's doing what he wants to do. Even just seeing the furniture sitting there, sometimes being rained on, is heartrending. How will it be helpful to Mr. Bennet's family if they are scurrying to find homes to be able to say, "Well, he at least was willing to admit it was his fault?"