A Slow Grand Prix

Ronald Strump is very rich and a bit strange. He organised a Formula 1 Grand Prix with a prize of $ 100'000. But the prize was not for the fastest car in the race, but for the slowest car. Ten drivers entered the race, but they thought: "How can we run this race?" One of the drivers said to Mr Strump: "We'll all just go slower and slower and the race will never finish." But Ronald Strump had an idea. He told the drivers what to do and the race was as fast as any other, perhaps even a bit faster. What did Mr Strump think of ?