I've seen people use the hand signals for turning, but never for braking, but I can see how it would be very useful for breaking.
Randomness... We were driving through Little Rock a few years ago and spent most of this time behind this car who almost always had its brake lights on. It took us way too long to realize the lights were really messed up and actually turned off when the driver used his brake. So dangerous!
I would use them for turning. . . but not braking unless both brake lights were out.
On a note related your randomness: we had some issues with our horse trailer lights and once the opposite turn signal went on from the one intended and another time the lights went off when you braked. Luckily we always check the lights before heading out and just had to unplug and replug the electrical connection back in. It was pretty crazy though!
Re: "Hand" Signals
I would use them for turning. . . but not braking unless both brake lights were out.
On a note related your randomness: we had some issues with our horse trailer lights and once the opposite turn signal went on from the one intended and another time the lights went off when you braked. Luckily we always check the lights before heading out and just had to unplug and replug the electrical connection back in. It was pretty crazy though!