Am I telling you anything you don't know?
I thought not.
One reason they don't work is that we have the idea that a diet is something temporary. We think, even if we know better, that this will be a short term change and after that we can return to having pop tarts. We can return to them if we wish, and we might, once the diet is over. (Can you tell that there are pop tarts in the house?)
What is needed instead is gradual permanent change. Small changes add up. This is a sustainable approach and it is what I did. So, over the next year I will offer various suggestions to change what you eat. Most of them you already know, but don't do. By focusing on one change a week, "muscle memory" can gradually be built up.
If you make radical change all at once, there are several risks. First you risk confusing your body. If your body thinks you are starving, it will reduce your metabolism. This is why dieters rebound, often to a new higher weight. They have reset their "set point" at a lower level and if they return to their former habits, they gain weight. 
A diet may force you to permanently adopt your diet caloric intake to be your new intake--permanent misery. Instead I will propose that you eat what you plan to eat for the rest of your life. Thus the ultimate name for this series of blog posts will be "Plan What You Eat." So don't lose weight too quickly. In fact you should not try to lose weight. Instead eat what you already know you need to eat, and then, as a side effect, you lose weight.
There are several other negative possible consequences to losing weight too rapidly. There is a connection between rapid weight loss and losing your gall bladder. 
If you lose weight rapidly you might end up with Richard Simmon's problem. There is a reason he wears baggy clothes. He has a lot of hanging skin around his midsection. Losing weight slowly will not eliminate this, but it will help. The body also stores toxins in the fat. If you lose weight rapidly, you risk drenching you body with all these toxins at once. This cannot be good for you.
Do not go on a diet. Instead gradually change your habits until your habits are healthy habits.
Today's "homework" assignment is Dr. Barron's presentation on the myths of obesity. Dr. Barron heads the UCSF obesity center. He notes in the presentation that the level you set your calories on a diet will become your new permanent level if you want to avoid weight gain.
Be careful, do not diet.
Note that you need to use your own best judgment on any "homework" I assign.