This is what my uncle was probably getting at:
"An unusual feature of the Saab drivetrain was a 'freewheel' (overrunning clutch). This allowed the transmission to run faster than the engine, such as when decelerating, or descending a long hill. Although such freewheels had been provided in other cars before as an economy measure,they were required in the Saab because of the limited lubrication in the two-stroke engine. A petroil-lubricated two-stroke requires lubrication according to its speed, but provides this lubrication according to the amount of its throttle opening. Where the engine operates at high RPM and low throttle (such as when coasting down a long hill), the lubrication provided may be inadequate. With the freewheel, a coasting engine could reduce its speed to idling, thus requiring only the small lubrication available from the closed, coasting, throttle. In certain higher-performance models and in later two-stroke models, direct injection of oil into the engine from a separate reservoir allowed lubrication to be a function of engine RPM and rendered mixing of oil with gasoline unnecessary.
Freewheeling was retained in the four-stroke variant, until the end of production and in the Saab 99 with the 1709 cc Triumph engine. A minor drawback to the freewheel, particularly for drivers unfamiliar with the Saab, is that it makes engine braking unavailable although it could be manually engaged or disengaged by a control in the foot-well. Fixed wheel engagement, using the foot, could be difficult, as it involved pulling a 'T handle' intended for manual operation"
Wikipedia though, so perhaps the electronic equivalent to my uncle.
PS He lived in Upper Cwmtwrch so this would have been a convenient way to get to Lower Cwmtwrch