SPIN - if you really want to gain an understanding, it would be worth your while to read Lanchester strategy. Specifically, "New Lanchester Strategy - Sales and Marketing Strategy for the Weak" (Vol. 2), by Shinichi Yano.
Cannon used the strategy of the weak to clobber Xerox, in Europe, and sent Xerox into full retreat, totally demolished.
It is not an expensive book. True to cultural form it is in comic book style.
If you can understand strategy, this book is very good introduction.
If your ability to understand strategy is anything like my ability to understand English grammar, then don't bother with the book. Some people just don't get it. I think every person has some subject that they just can't comprehend. Your's might be WAVX.
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