One difference is that the Diet Solution Program is not a short term quick fix for being overweight. In fact, this diet is about making lifestyle changes and taking control of what one eats more than how much one eats. It does not make inflated claims about how much weight one should lose in a week or a month. In fact, the only claim made is that one will reach his/her ideal body weight if the plan is followed over the long term.
There is also a relationship between the calories consumed and the amount of exercise one gets. The Fat Loss diet does not mention any need to exercise. Instead, it relies solely on the "confusion factor" to trick the body into burning fat. The Diet Solution does not specify what types of exercise are needed to maximize weight loss, but it does mention that exercise is also one key to losing the weight and becoming more energized.
Back to the original question, does Fat Loss 4 Idiots really work? Yes it works for the short term. However, for long term weight loss and improved health, diets such as the Diet Solution program is a superior choice. It offers more flexibility in the foods one can eat and in meal preparation.
It also recognizes the need to exercise as part of any weight loss regimen without recommending that one push to the point of complete exhaustion or starve one's self into losing weight.