Then there's the stubborn reluctance to accept fact....
A friend of mine insists she once drove from Salisbury to Leicester University in an hour and a half. Now that's 148 miles, requiring an average speed of 98.7 mph. Autoroute reckons on about 2hr 20 min.
"Surely mean two and a half hours?"
"Are you calling me a liar?"
Even an impatient driver like her, who once claimed that it was 'impossible' to drive at 30 mph on a road where she'd been pinched for doing 40 mph, couldn't possibly manage a 99 mph average for 90 min in an diseasel Vauxhall Astra estate on the A303/A34/M40/A43/M1.....
German SatNavs are indeed something else! A few years ago, a car a colleague and I once hired at Hamburg airport had one of those, with a female voice. It was quite polite initially "In dreihundert Metern, biegen Sie bitte rechts ab", but became more insistent until eventually screeching "JETZT RECHT!!" like some whip-wielding, leather-clad Brunhilde in a Hamburg dungeon (I would imagine...
). I half expected "You haff been a very naughty boy - now ve must punish you!" to come next, but instead there was a pause, followed by rather a pouting "Wiederberechnung" in one of those "You've always got to know best" voices....