From America’s Test Kitchens "The Best Recipe" cookbook (which I like better than the show): they agree with the 80/20 proportion and say anything over about 21 or 22% fat will wind up being left in the pan anyway. They recommend buying a chuck roast and having it ground or grinding it yourself and say in their tests doing so the result came out at about 20% fat content when checked with a Fat Analyzer device. That’s what I prefer to do, grinding it myself. I presume they were buying choice rather than select beef.
Interesting facts I didn’t know: labeled fat content on a package of meat has to be accurate no matter where processed but the content, in terms of what cut(s) of meat were used, isn’t controlled or assured unless the meat was processed at a federally inspected meat processing plant.
From Russ Parsons’ "How to Read a French Fry:" the perceived juiciness of a piece of meat has to do both with how much moisture is left in the meat when cooked but also how much the saliva glands are stimulated. The intensification of flavor which results from caramelization of sugars on the surface of the meat (browning) stimulates the salivaries more than that grey stuff the fast food places specialize in.
I like a little ‘crust’ on my burger patty — not blackened – with a bit of pink left in the center.