Even the best sat-nav systems can be confusing, and drivers who slavishly follow their directions can quickly find themselves on the wrong side of the tracks.
Indeed, earlier this year one hapless motorist became the first to be convicted of driving without due care and attention, after unquestioningly following his TomTom's instructions to the brink of a 100ft drop.
But the consequences can be more serious - or at least harder to undo - when the vehicle in question is an articulated lorry weighing up to 40 tonnes.
Rural communities across the UK have been hassled with noise and blighted by damage from heavy goods vehicles taking rat-runs through roads that are too small, while earlier this year a truck delivering for Tesco had to be recovered after a sat-nav problem left it stranded in mud in Snowdonia.
Now industry body the Freight Transport Association (FTA) has teamed up with TomTom to offer a system which is said to be wise to the kind of low bridges, narrow lanes and fragile bridges where truckers can find themselves in trouble.
And while FTA policy manager James Firth said the system would help in "preventing chaos along our urban and rural road networks", he also issued a disclaimer and a warning for anyone tempted to place too much faith in a gadget.
"However impressive the technology, there can be no substitute for common sense," he cautioned.
"Drivers should not just rely on sat-nav instructions to make their decisions for them, but should pay attention to other indicators, like road and bridge signs."
