Nothing to do with traction problems in fields, but a bit to do with parking facing downhill at all times.....
At one point, in one of the Carltons I had, the battery was knackered - it'd start if you'd left it a short while, but not overnight, and a bit dodgy if it was an hour or more - so I'd always park it facing downhill if I was going to be stopped for a reasonable while, and when I got home, where there was a very slight slope from the drive out into the cul-de-sac, I'd keep a pair of ramps handy in the boot and back it up onto them to allow easy starting in the morning.
Which was nice.