Let's cross that bridge when we get there. In the meantime, I more regularly see the people whose BMI is highly correlated with their body fat percentage; and,

Let's cross that bridge when we get there. In the meantime, I more regularly see the people whose BMI is highly correlated with their body fat percentage; and, one of those requires a scale and a number that doesn't change after your early 20s. The other one requires a tape measure, calipers or an immersion pool.