I rode 125 miles today in the heaviest traffic I have ever seen. I counted on 4 occasions where the last guy signaled a closed fist indication he was last in his group and another group was close behind. It's not the norm for this to happen but none the less more frequent than rare. The hand signal system is flawed and honestly, if you think about it, it gives you permission to be less cautions because in your mind you think there is less risk of a sled approaching when in reality there may just be a sled from a different group. How many times have you changed position in a group and signaled the wrong number, it happens.
What does a hand signal instruct you to do differently than you would normally do? Ride in the center of the trail? Ride more aggressively? If you were to ride as though there could be a sled at any time, would that not be the best system to ride by? Hand signals alert you to be cautious and that's good thing. it's even better to ride cautious all the time. I cannot think of a single instance where I have benefited from hand signals but I can tell you of instances where signals have nearly caused a sledder to loose control, signal errors. Supposedly a few weeks back a women was killed as she lost control of her sled while signals and struck by an oncoming sled. If it makes you feel safe than there is nothing wrong with signaling but riding with a high level of caution cannot be improved upon with signals.
BeerBellyBob sells the "ride light" for $78.50. It's a small devise about the size of a flip phone. It's hard wired in so it's on all the time and depending on your position in the group, you select the correct color for your position. I nice function of the light is a flashing yellow meaning you need help. That factor alone could be very useful in an emergency.
I'd much rather see people devoting more attention to their skis and track for safety. If you ski's are junk or carbides severely worn your handling is greatly compromised. Today the traffic was so heavy the trail became loose and with a decent base, the loose was making for the sleds all over the trail. I came upon a 2 person group with a women on an older doo and she about lost it a few times. I felt bad for her as she was not enjoying her ride. She rode at about 25 miles an hr and was all over the place. I was on a 91 Yamaha with a short stiff suspension. I run Simmons skis and 96 picks down the center and the sled is very safe. The rear does slide in loose trail but just give er a little more gas and she straighten right out. Get a good set of skis and the right combination of track to fit the skis and the safety factor increases tremendously. If you have never experienced aftermarket skis than you are seriously missing out and at a greater risk of darting or loosing your line in a corner. Running a sled with precision skis and track picked for acceleration and braking allows me to run faster and with more confidence keeping the fun factor at a high level while maintaining a very safe cautious ride. There is a lot at risk on the trail and operating safely has many aspects. To me, sled set up far outweighs signals, something to think about.