I first heard about this book from the Clarineat Podcast "In Memory of Harry Sparnaay" episode 74. The interview with him was delightful and I decided I wanted to get the book. I didn't receive it before heading over to Banff for our music residency but the wonderful library here has it! I am finding it so full of information and inspiration that I can't help but share it even if I'm not finished.
There are many extended techniques described in this book including possible notations for them as well as examples which make this book useful for composers as well. Although not all the translations use language that I am used to it reads well and I find myself laughing out loud, which you wouldn't expect in a technique/history book.
I am so excited by this book and find myself working to incorporate the techniques into my practice routine!