It’s ok to take shortcuts, when you understand the problem. That’s why you are able to take the shortcuts and get the proper answer.
However, Common Core is trying to teach those short cuts before the kids have mastered the material. It’s the same reason why kids literacy rates are lower from a generation ago, they were taught to memorize words with no understanding of the phonetics behind those words.
Please present evidence that the workbook in question did not, in an earlier lesson, teach a kid how to add 7 to 7 directly. If you have no such evidence, then you have no argument.
The other day some moron scribbled a bunch of numbers on a piece of paper, took a picture of it, and posted it to FR as an example of Commie-core, and the predictable outrage began. I find it disturbing that so many people on FR can be so easily and willfully be duped into a 2-minute hatefest.