I'm a registered life and health insurance agent. Insurance companies cannot set the statistics then charge premiums by what they think is the norm. Its illegal and the government don't allow it. These statistics are based on millions of people, not a companies idea. If you'll read no-one said anything about EXACT bf calculations also. Actually just the oppisite was proposed,,,,, "Although not exact".
Not trying to argue but you have no point to be proven. You can weight 10,000 lbs. and be 5% bf. However if your currently 200 lbs. with 15% bf then you can not also be 200lbs. @ 5% at the same time. With your CURRENT muscle mass why is it so hard to get an idea of how many lbs. of bodyfat you should loose to drop say 10%BF? If someone is unable to make these calculations for themselves thats fine, but I can do the math for my own calculations and be very very close.