It's difficult to see when the 80% will ever pay off. They're a year in and he's got 94% health - but with that limit in place that's an effective battery capacity of 73% (0.94*0.8). At the rate that the others' batteries are degrading it's going to be close to 2 years before they even hit 80% capacity let alone the 60-70% that would make the 80% limited battery have better total real battery time. And at that point what are we saying? You're trading a good chunk of your battery in the first two years of its life for a few percent more several years into owning the phone?

It seems difficult from these numbers to see when, if ever, this choice is going to pay off for the people who opt in.