By Thomas Bristow For many, the driving range is a source of freedom. A place to blow off steam after work or enjoy socially with friends. For others, it’s where the real work happens. Amateur golfers often spend hours smashing spheres in a bid to hone their game ahead of a club championship or a round with their pals at the weekend. But it’s all too commonplace for a large portion of those golfers to go just ‘hit balls’ without thinking much. Before you know it, 100 balls have been hit and not a real lot has been learned. If you’re looking for some guidance, following Dustin Johnson’s practic…