However, I feel you have committed an injustice to financial advisor Andrew Tobias on the page, "Math was the most difficult subject I ever…" In point 10 it is implied that he added the 10% savings on four purchases to arrive at total savings of 40%.

What he was referring to was the return on an initial outlay (the cost of a case of wine minus the cost of a bottle). This (apparently) gives an annual return of 177%. He explains this in detail on his Web page:

https://www.andrewtobias.com/bkoldcolumns/980901.html

Of course, savings on overall purchases remain at 10%. If he is guilty of anything, it is of thinking like a financial advisor and not like a household budgeter.

Cheers

Brendiggg

But must tell you that Tobias' page does not make an easy reading. Will look it up in the morning with a cup of coffee in hand.