Yeah I don't know the original post, but for awhile I did the Grocery Game, if I remember correctly. You'd pay something like a dollar a month and select three regional supermarkets. Then they had calculated when to wait for all the specials. So things would happen like, you'd get a coupon for some product in the early March from the newspaper, and then in May those same products get already marked down and the store does some buy-one-get-one-free thing or something so you can essentially get it for nearly free. When I did that my bills were at least 50% off the original purchase price, but you have to do it religiously.
The SNAFU is that most of those things were for processed foods and the like. I really buy mostly staples now (flour, sugar, produce, dairy) and then make a lot of stuff from scratch (more and more every day). The savings therefore really aren't there for me. Another SNAFU was that there would only be apparent savings on certain things. So, yeah you "only" paid $1 for that specialty box of that Birds Eye frozen corn with basil, but the bag of just plain jane regular frozen corn with twice the weight was the same price. So overall, you want to save on your grocery budget, cook from scratch. Maybe even check out the Hillbilly Housewife website instead.