NP13 - I think these are some good questions/points you bring up.
Let me tell you a story about "measuring" though. When my older son attended events (all were reputable...for example Area Codes among others) his junior->senior summer, some of them did measure him. Not very well though. There was a range of 20 pounds (no way) and 2 inches (no way either).
How could this happen? Still don't know the answer.