A mature review is in order, I think. First up, I have read and understood both these books thoroughly. For the past 20 years I have been teaching undergrads and also performing magic & mentalism mostly for educational institutions.
When this was first released last month, I remember the price was $3. But by the time I got around to getting it, it got doubled to $6. So I went ahead and got Advanced Brain Knewmerology too for $3 while I still could. And on I am happy to say they are worth every penny I spent, if not more.
Although the author credits Martin Gardner for the origin of the basic idea, the extraordinary presentation given here which couches the math into a mystical theme elevates this to a whole new level.
Let me throw a little more light on the process itself without tipping too much. This routine is performed on 2 participants and NOT 1. Performer does not ask 'her' to declare ANYTHING. It is the 2nd participant who declares his final result. And you still reveal her thought - there is a beautiful "logical disconnect" if you understand what I mean.
And these days, you ask someone to add 2 & 3, they would pull out the calculator on their mobile phone anyways. You hardly find anyone doing math 'in their head' anymore.
The author has clearly mentioned "announcing" and "non-announcing" methods in these books. And as far as Advanced Brain Knewmerology is concerned, it is far more stunning and mind boggling.
Overall, a brilliant routine, I feel. Although it needs presentation skills and some basic audience management skills but these cannot be taught off the shelf.