This diet is very unique. It rotates your calorie intake everyday so your body doesn't plateau. It rather tricks your metabolism. Every 17 days you start the regiment over. As a vegetarian I had to create my own. I suggest you at least tade a look. Just google 17 Day Diet.
This has been around. My diet starts over every 7 days. It just depends on how often you change it up. This kind of diet isn't as mainstream as it is much more difficult than just setting your calories to 2000 and you can forget about everything else. This takes more work, thus the average person isn't going to adhere to it as much.