It is much harder to measure muscle mass at home, or even at the doctors office. Different methods show very different results when people are measured at the same time.
We need a simple proxy method for estimating the healthy weight range.
We need a simple proxy method for estimating the healthy weight range.
Obviously not as good as actually measuring muscle mass, or anything more scientific, but I think it would be a pretty trivial way of making the BMI estimate another chunk better.
The assessment you're trying to make just isn't reliable.