I remember back in the mid-1980's pulling a twin axel U-Haul with my car. At about 55 the U-Haul would begin to twitch. When it began raining the twitching stopped and the trailer began pulling normally. As for the guys lights being out, he was probably unaware. It's happened to me, in fact I was pulled over once by a state trooper for no trailer lights. It turns out they'd come loose at the connection. It was another danged U-Haul! I pinched the leads slightly with a pliers so the connection wouldn't pull apart and was on my way with a warning ticket.
I've always wanted to write a book about the various U-Haul misadventures I've had over the years (and I've had a bunch!). Adventures in Moving! would be the title.
Steve
PS to U-Hauls credit they've gotten much better, back in the 1970's they were awful!