Last part!
Here's the funny part to exemplify it is all relative to people's experience...
After my pressure class, I went to a basic daily 4WD maintenance class. I always want to learn. It was taught by ANOTHER member of the Camel Trophy guys and had been across Africa many times amongst other locales. Another great class. At the end: "any questions?"
A guy asked "what do you use to air up tires?" He said "what do you mean?" To which the guy said if you air down your tires to get through sand or whatever, how do you air them back up". Answer, "I don't air down my ties!"
What? I'd just gone to a class in adjusting tires pressures, by a Camel Trophy guy, and now this guy says "don't bother". He explained his rationale and he is always in a Land Rover, with the stock tires at the recommended pressures and these things were built for this kind of stuff so why tamper with it. Yes, if he got stuck or it was behaving terribly, he'd deal with it and maybe air down but the vehicles he drives basically don't need it much or it just isn't worth the hassle.
So there you go, even amongst Camel Trophy pros, their combined experience tells me "it depends"
There is no "right" answer to this question!
;)
