The article @BoxingRobes posted uses RB's NFL weights - https://www.footballoutsiders.com/projection-points/2020/running-back-growth-potential-starts-size
So that 29-31 optimum BMI is for NFL RB's - it's not using what those RB's weighed in High School.
You're confused & incorrect on both posters & data
Your discussion/data is literally meaningless if you continue comparing 16-17 year olds weights to 21+ year olds weights and this is why I and others have shown that HS measurements don’t have the same correlation to college success.
While you did not post the article, you