All this is pretty obvious and vague advice. The only potentially ground-breaking conclusion the study appears to have arrived at is that the "variety of foods consumed is just as important as the volume in relation to a person's weight." In other words, they found (as many other recent studies have also found) that weight is not a simple calculation around calories consumed. It's the quality of those calories that counts.
We would have liked to see the study take their research further, and measure high quality foods (organic, raw, whole) instead of simply focusing on food categories (fruits and vegetables).
One way to look at the Spartan Diet is to view it as a very high-quality version of the Mediterranean diet. Here's how the Wikipedia summarizes the Mediterranean diet:
[The Mediterranean diet] "emphasizes 'abundant plant foods, fresh fruit as the typical daily dessert, olive oil as the principal source of fat, dairy products (principally cheese and yogurt), and fish and poultry consumed in low to moderate amounts, zero to four eggs consumed weekly, red meat consumed in low amounts, and wine consumed in low to moderate amounts'."The Spartan Diet takes this much further, and bans sugar and all sweeteners except raw, unfiltered honey; insists on organic produce; bans all dairy products and domesticated animal meat (most wild fish and game is OK in moderation); and has many other elements that make it the "healthiest diet in history."
The Spartan Diet will be detailed in an upcoming book called, The Spartan Diet. Go here for more information on the Spartan Diet.