I remember BP covering the issue of sound before and it brought back to me, as NR's post does, just how
really quiet it can be when you're away from the hustle and bustle - out in the hills - on a mountain top... (wistful sigh!).
How soon and how readily we adapt to the silence may depend entirely on experiences recalled so yes, we should make every effort to do as NR suggests. (Highlander - can you put up with someone in a bivvy at the bottom of your garden?
)
When the time comes, the sound of approaching engines, heard long before their arrival (remember wind direction and strength will play a part), will herald the forces of 'law and order' or the bad guys (might be the same beastie!) as they will probably be the only ones with access to any remaining stocks of fuel, by coercion in either case! It'll certainly be a sound that shouldn't be responded to by rubbernecking...