Bethwaite is extremely knowledgeable. The book explains what, how, why, where and when certain weather patterns occur in detail that the reader can understand. Then continues to give tips to the helmsman and crew what to do in these conditions. I haven't gotten to part 2 yet where he talks about how to handle the boat for maximum VMG around the race course in the different conditions. A little background in fluid dynamics is helpful but not necessary. I would very highly recommend this book to any sailboat racer, at any level, who would want to advance their skills and knowledge on and off the racecourse!
Incredible book for learning about weather and high speed sailing. Not for beginners by any means, but extremely interesting if you've been sailing for years and want to take you sail trim and racing to the next level