Southern California - Suitabilty of Scales in Organized Long Rides

After suffering through another long ride in the heat where I lost more than 5% of my body weight, I realized I had a drinking problem. I thought I drank enough water and I surely did not feel thirsty during the rides. This got me to thinking "What if we had scales at each checkpoint so that we could monitor our weight loss or gain (some of these rides have some great spreads) during the ride ?". If I knew that I was 3 lbs down at checkpoint 4 maybe I could think clearly enough to take on more water.
Some Ultra Marathon foot races weigh you at checkpoints and will not allow you to continue if you fall below a threshold.
Is this worth requesting from event organizers?

If you're down enough weight to be noticeable, it's too late to correct it. The only reason to have it would be as in the example you state - to pull people off the ride.

Scales are notoriously inaccurate, even from the same manufacturer. I wouldn't be happy if somebody pulled me from an event because of this and I was feeling fine.

Plus, and I don't know if you've ever organized a major cycling event . . . There are so many details to attend to, that providing scales and calibrating same for each checkpoint would add yet another level of difficulty for the organizers. It's difficult enough as it is . . . don't make it worse!

And magicant is right, by the time it shows up as weight loss, it's too late anyway.

Rick / OCRR

If I drink at least one bottle per hour I have no problems with dehydration.