Yes, everyone in the military knows how inaccurate the current system is. But, it is a standard that can be defended and justified to the D. O. D. (Department of Defense). It all boils down to cost- just like in the commercial/civilian sector. It takes ten minutes of instruction to be “trained" to take measurements, and be able to control how a person's military career goes. Other than a tape measure and charts, there is no cost involved.
The previous system used a “body pinch" test. You went to the hospital where a technician would pinch certain points of your body, and enter the results into a complex program. This was a very expensive, slow and cumbersome process. Only medical personnel could perform the test (whereas any first sergeant can do the tape measurements).
They had to be trained, and the training wasn't a quick ten minutes. It required several days down at Lack land, and they had to know the difference between pinching vertically versus horizontally, where to pinch, how many body points (arms, waist, thighs, neck) needed to be sampled, etc.
Usually only a handful of personnel were trained on the entire base, meaning long wait times to get the entire base processed. After only a few years the military realized the system just wasn't working. They couldn't process people fast enough and the trained people were constantly being reassigned, meaning more people had to be trained.
At the same time, if you had someone sent TDY or deployed to a remote location, there would be no one available to measure people when the need arises (usually the measurements were taken in your birth month, in conjunction with your annual physical assessment).
So they came up with the neck/waist system. The backlog of personnel was cleaned out within a matter of days; first sergeants now had “first hand" exposure to the fitness of the squadron's members. Even though the military acknowledged certain “inaccuracies" in the new system, it allowed for rapid assessments of the troops. If a commander thought someone was getting a little portly, it only took a five minute trip to the first sergeants office to settle the matter.
Of course, if you are found to be unfit and further testing is required, there were other tests, performed by qualified medical personnel, which would offer a definitive assessment. The military can't JUST use the tape measure to justify kicking someone out of the military as unfit.
So basically, the tape measure system is the first, inexpensive, line of defense against unfit troops. It's the quick way to separate those fit enough to not worry about, from those that required a second look. Why do expensive, time consuming evaluations on everyone in the military when only 5% need to be examined under a microscope?
There is really no reason to send someone that is unfit into a combat zone and think that he will be fine where he is. You have to think about all the others that are in that platoon. If the person is unfit and he got hurt there is really no way that platoon will be able to bring him to safety if they have to stop a lot just to let him bring or to drink. Even if that unfit troop was not hurt. He or she could just be a really big threat to that platoon or he or she could end up cost everyone their lives.
Victor Epand is an expert consultant for http://www.WarGear.info/ . WarGear.info carries the best selection of military clothing , war gear, and combat accessories on the market.