Is Quantum Speed Reading really useful?

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Quantum Speed Reading (QSR) is a reading technique developed in Japan in which a reader simply flip through the pages. This technique does not emphasis on reading the written word. I found this technique on a website on the day just before my exam. Since the portions were so vast, I thought of trying this technique for my exam because it seems to be fast. The result was disastrous. I got a very low grade for that subject. Does this technique really work or is it a crap or did I apply it in the wrong place?