You agreed that a body totally immersed only measures volume. Makes no difference whether it is in free fall or not.
If you think about the procedure for obtaining fat percentage (measuring body density) I'm sure you will reason out the necessity of obtaining body volume. You may even come to agree that using a tank of water to measure a person's weight is overkill. I'm not involved in that trade, but I will bet you a week of posting privileges that immersion is used to obtain body volume, and that if they didn't need volume, they could simply use a weight scale.
Never said it wasn't. I am not arguing that. I have had my body mass ratio's done. I was put in a tank, they got a displacement reading while I was floating to calculate my mass accurately. They then had me grab a bar and pull myself completely under water and they then got a volumetric measurement. The computer then calculated everything from those measurements using known human body fat to muscle to bone ratios. As I recall, they did not weigh me on a scale because with the computerized equipment being used, it would have been redundant.
Certainly, they could have used either a spring scale (fairly inaccurate) or a balance scale (fairly accurate) but then you might introduce operator error in inputing weights collected from each instruments.
As to bets with posting privilege stakes, you have proposed that to me before I believe. I do not play. I do not believe these micro-issues are important enough to see you gone for an enforced period of time so long as you argue your positions civilly. Soliton (remember him? He's the character that started this thread... ;^)>) got his enforced time-outs because he was never civil for any length of time. When he was refuted with facts and peer-reviewed science he always resorted to ad hominem attacks on either the sources or the person posting.
Frankly, I am as much on your side as on the sides of the others involved in this discussion. My purpose is to critique the science claims either way. I will even correct myself when I make a mistake.
I am not a creationist, nor am I an evolutionist. I see too much evidence for an ancient Earth to accept that it was not in existence 10,000 years ago. However, I see to many statistical accidents that have to work out just right, in contravention of laws of entropy, for evolution to continually go from the simple to the complex, simply by random occurrences. Too many evolutionary, mutational "improvements" are not statistically significant enough to assure the replacement of the previous un-mutated animals and plants simply by survival of the fittest; the "fittest" just aren't that much more fit. I also find far to many assumptions based on assumptions based on even more assumptions in the ancient studies such as archaeology and paleontology. Often, when you track the assumptions back, you find they are baseless, or merely dogma. Too much in science that was considered gospel truth ten years ago, is now known to have been falsified. Go back 20 years and it is even worse.
It wasn't too long ago that catastrophism was considered a crackpot idea... but now most paleontologists accept that catastrophes are major life changers. Evolution science has moved from a "belief" that the mode was a steady progression of mutation and survival of the fittest to concepts of punctuated evolution where some event makes for major mutational alterations and extreme die-offs of animals that were once "the fittest."