"Negative Math" book by Martinez - any feedback?

[TrailingDots]

Hi,

I'm about half-way through the book "Negative Math - How Mathematical Rules
Can Be Positively Bent" by Alberto a. Martinez.

The history of passionate rhetoric by even the great mathematicians is fascinating!
This provides a wealth of information about the centuries of arguments relating to
negative and imaginary numbers! (Disclaimer: I am not associated in any way with
this book - other than a passionate reader.)

What is not clear to me is if any of this material is still relevant to "modern" math?
I'm about half through this book and am not clear if these arguments have ever been
settled. It's obvious that most math teachers could not justify many of the arguments
for and against negative number interpretation. If I tried some of them in the
classroom, I would certainy be branded a trouble-maker.

So, do variations in math such as described in this book prove useful? Do useful or
even recreational math problems exist using a solution where +1 * -1 = -1?
Or any other of the many strange (to me) interpretations?

What do other people think of this book's historical usefulness?

Thanks