...to a "T" when it comes to food portions or do you figure it out for yourselves?

That is my question. I know that there are not a lot of you out there that are zone-ing, but maybe you can still answer my question. In the book, there are portions layed out that are supposed to be in 9g. carbohydrate blocks. What I am finding out is, when I figure out the blocks on my own, using the nutrition guide put out on the USDA datebase,my portion sizes are a lot different.

So, do most of you out there follow what the books tell you, or do you use your own calculations?