There are only so many amino acids your body can use. Your body has an "amino acid pool" viewing a protein source only by itself dosent do it justice. All amino acids are going to this pool. (if not oxidized) therefore Biological value only matters if you eat soley ONE kind of protein source over the course of a whole day.
The stuff hernon sells are hydrolized collagen amino acids - sure i agree Liquid BEEF sounds cooler
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. You could simply buy almost any other liquid amino acid product add some glycerine and you have a cheaper version of "LBAs".
The question we have to ask ourselfs is if amino acids get "lost" during digestion if we eat "normal" food. And do more amino acids reach our amino acid pool when they are predigested? AFAIK approx 90% of whole food proteins do reach the amino acid pool. So i highly doubt you could make the same gains using 80g Protein predigested to compared 300g from whole foods.
It is true though that 1-1.5g Protein per lbs Bdwght is sufficient. I feel that no more is needed.
Keep in mind that Phil Hernon sells the product rather agressively and attacks anyone who has to say something against it. Most people who report good results do so because of high glycerine ingestion which binds a lot of water within the muscle cells therefore causing more pump and a dry appearance.