If rallies weren't so long back then, group B would've maybe survived. Henri complained couple times that they drive 4,5 hours equal to 1000 Lakes rally and there was still special stages left in Corsica rally, so they at the very least drove 5+ hours on 400-600 horsepower cars. Nobody can fully control them that long and still drive as fast as possible, maybe full control for 2-3 hours but not that long.
