I've done the 3-Day Diet several times, and I was quite successful with it. However, it's not because you're eating things at the right times or in the right combination. It's simply because it's very low calorie (especially the second day), and most of the foods are packed with water.
I'm almost ashamed to say that I've used it so much, because I know it's not healthy or permanent. It IS a good motivator to get you started. Seeing those pounds come off in the first week always got me to stick to it. Also, I used it as a tool to get myself in discipline mode. After spending 3 days on the diet, you feel like you're feasting at 1300 calories!
I have seen no difference in results when I've changed the foods around throughout the day. Just make sure you distribute it evenly throughout the day, or you'll end up binging on cookies!
Also, on the second day, eat something extra. I added it up once, and it only allows for 800 calories- by far the lowest of the three. I personally end up cranky and with a headache all that night if I don't throw in an extra piece of fruit or something.
Don't depend on the diet to be your weight loss. If you do, you'll just gain all the weight back as soon as you get off of it. Instead, use it for 3 days, then start a healthy routine of eating right and working out. That's where the true and permanant weight loss will occur. If you feel yourself sliding, try to 3-day diet again.
I've found this pattern to work well.
"The future is no place to place your better days."