I do it all the time in rural areas.
A slow moving farm-truck with a load of hay/straw can be a danger on the 2-lanes...especially for the TR/TR/TR that need that extra time and istance to brake safely.
Now that no-one is using CB radio anymore, headlamps are the way to signal and keep others safe.
Years back we had a CD in the car on channel 19, so did a majority of travelers. If there was a cop car on the road, it was breaker break, bear at mile marker (what ever) If another car was traveling with you, you dialed to another channel for private conversations.