What I really got out of it is that you're not trying to make them "behave next time", you're never going to give that one lecture or make that one punishment so memorable that they "think about it next time". What you are going to do is halt the spiral that humans tend to do after they mess up and you're going to make it a family habit on the parents side.
The reward system, I really butchered it, and it worked for a while and really gave us a good conversation starter for my husband's main gripe with the boy, which was, "you don't do what I say and yet you want me to do something when you ask". My butchery was that I made two coin purses and gave Wyatt eight quarters. If he Messed up I took one of his pieces of eight. If he had five pieces of eight he could ask for anything and maybe I'd say yes, maybe I'd say no. (play outside, go to the park, watch tv). If he had less than five pieces of eight the answer is "no". They get replaced every night unless he goes lower than 3 pieces left in which case he does something to earn them back.
I quit doing this because the book says don't do a credit system that takes away from the kid, I'm trying to figure out how to simplify the system in the book. Jack's mom posted a good system where you give a coin for every random increment (30 min) of time spent in good behavior, which is traded for tv, park, etc. That is more in line with TNH. I want to get more in line with the system because it's easy to share with other adults. The hubby liked the pieces of eight. When I explained the pieces of 8 to a neighbor (who asked how I discipline) he said i was grounding.
Another drawback is that by teaching your child to covet pieces of eight, he may later choose to pursue a career in piracy on the high seas.
I don't think that the TTDC system is really complicated to administer. We had a sheet of things to check at the end of the day (anyone is free to PM me if they want a copy) and we would run down it in a couple of minutes at the end of the day. Certain types of severe misbehavior would suspend privileges immediately. I initially thought it would be complicated, but it really wasn't.