BMI is like that funny clunk the car makes when you put it in reverse, it's an indicator that there is an issue that may need further investigation.
Actually BMI would be like looking at your mileage and comparing it to a generic car mileage chart that purported to tell you when your car was going to conk out. Regardless of make, model or year. That information would be virtually worthless for a mechanic, since one car with good service may be perfectly fine at 150,000 miles while another will be ready for the junk yard.
Even more, BMI would be like comparing your mileage chart to a car mileage chart made in Europe during the early days of automobiles.
Looking toward your feet and not being able to tell what colour shoes your wearing, because there is a spare tire big enough to fit a city bus in the way, is another indicator of the same thing.
No, it isn't. BMI does not tell you how big your gut is. I've never lost sight of my shoes in spite of my high BMI.