premise: There are now several million cars in the UK using satellite navigation (satnav) systems. These mcreasingly popular satnav systems mean that motorists no longer have to read maps while they are driving. There are two other major advantages: reduced journey time and reduced mileage (and thus fucl consumption) on unfamihar routes. System improvements have made these devices much more features. Although some safety surveys highlight the dangers of operating dashboard devices while driving, research conducted by one satnav manufacturer showed that nearly 70 per cent of drivers felt calmer and more focused on the road when using a satnav system.
hypothesis: The passage suggests that a satnav system can make navigation more efficient.