Hi, saw your post on the Amazon too - will reply there as well.
You actually do need the other books but you can try just covering this one and seeing if you get to a good level. This book has the basics/foundation that you can't get around and must have for a good score. the individual books have mostly strategies and tools to help you spot errors/mistakes/traps, which you could technically do without and still get a good score.
So, the answer is - maybe. I would cover this book very well and then focus on the areas that are lacking. Does that make sense?
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