
However, I'll chime in anyway.

Any 4x4 gathering, from two vehicles and upwards, should have a drivers briefing at the start, and a smaller one each morning before setting off, to set the tone. It's just the done thing.
Even if it just takes one minute and only involves a couple of sentences, it should be a habit that ALWAYS takes place and doesn't have to be pedantic or regimental. No finger pointing. Just what is coming up on the day, comms plan maybe if you're that detailed, and what not to repeat from the previous day. Then everybody goes off happy and informed, and problems don't escalate. "Guys today we are heading west, everybody on channel XYZ, maintain convoy discipline so always keep the guy behind you in your mirror, and Pietie is going to be sweeper. Oh ja, and another thing, remember to bury you kak properly"