First, Stuff that produces results is never out dated. The methods Arnold and company were using are 50 years old by now... But I would bet my last dollar they would still produce great results today.
Second, Berardi's ideas were largely for body composition. Right from the 7 Principles - "Moreover, many people can achieve the health and the body composition they desire following these 7 rules alone." - Its basically a guide to achieve "good" body composition with minimal effort (ie - not counting every oat that passes your lips)
I doubt there are very many top level power lifters worrying about having P+F+C meals. Body Builders however have used the P+F and P+C ideas with great success for decades now. Obviously having a few PB&J's a week is not going to turn you into the Michelin Man, but there is a reason things like Donuts and Ice Cream are typically considered junk food.
And Third, All of these ideas should always be thought of as "jumping off points." Meaning try out the idea, track your progress and adjust as necessary.
The ideas might be "old school"... But sometimes that's the best school to be in. Did you have any specific questions about the ideas? Or just wanted a general feeling from the Nation on the overall ideas.