> People charge at work from 68% to 75% because is convenient.

Isn't that almost the best possible way to charge a Li-Ion battery?

It is.

I mean, keeping it closer to 50% might be better, but the returns are so diminished by that point that it's a rounding error of a rounding error.

I keep my limit to 75% unless I have a long drive planned, and nearly all my charging at home. I'll probably have <5% degradation after 100,000 miles.