Vince loved the protein and fat diet - I believe he called it the Maximum Definition Diet. I used Vince's diets when preparing for contests with great success.
Basically I was eating/drinking dozens of eggs a day (anywhere from 1-3dozen depending on what else I ate). Whole eggs are a perfect food (and cheap). I had only 3-4 meals a day, but between meals I would take a handfull of liver tablets. The most important supplements will be the enzymes, liver tabs, and EFA's. These will help with digestion and cravings.
Make sure you take in only fat and protein, as there are carbs hidden throughout the Standard American Diet (S.A.D.). Also try to limit your processed food intake (ie. use butter - not margarine, etc.) And drink plenty of water - hyperhydration. Every 3-4 (sometimes 5) days have ONE carb only meal. Don't make it too big, and don't eat crap...I guarantee you will feel like crap. Hell, I would get bloated after eating a small bowl of rice while dieting.
The longest I used this diet was 12 weeks. But honestly by week 3 or 4 it was no big deal and could have gone on much longer. But Nick would have me vary between the definition, hormone, and mass diets. Despite other's "beliefs", quality research shows no problems using this diet long term (research the Eskimo or Inuit Diet, or read Will Brinks info).
Hopefully I got the major stuff. Vince said that creating a the illusion of a muscular body was 85% nutrition. That means you MUST eat correctly, assuming you are already training correctly.
As I recall Vince said that raw, fertile eggs stimulated the endocrine system and therefore naturally increased growth related hormones. I would drink the shakes he recommended throughout the day for a couple of months (8wks) and switch to another more moderate diet (ie. mass or maintenance). These shakes consisted of raw eggs (12), cream, sometimes wheat germ, banana, and a milk/egg protein (now I use whey)... among other things.
The results aren't mind blowing, but they are noticable. First, recovery and growth happens more readily after just a week on this diet. Second, little aches and pains (low back, etc.) seem to diminish. And finally, I swear I feel a stronger pump during and after training. My body appears to lose fat and gain muscle, but nothing too dramatic (its not magic). And, barring injury, my weight and/or reps increase steadily.