Agreed, I almost always have my GPS muted, just using it as a moving map with live traffic information (Google Maps FTW) and ETA. And I look at the ETA and journey time before I start to see if it looks reasonable.
That said, the Belgian woman was lying and using "GPS made me do it" as cover. No one is that stupid, for one thing you can't drive for two days straight without breaks and rest, which would be a dead give-away to anyone with enough cognitive function to actually be able to drive. Not to mention signposts in several different languages along the way