It is possible to engineer lessons, but you must not ignore the variability of learners, and fewer factors affect the results of a lesson greater than the individual learners.
I often buy books at used book sales that I find offensive (The Bell Curve is an example) and I leave them in my library indefinitely. Should I continue this practice? Is it OK to take the books for recycling?
The most distressing aspect of public discourse recently is that it has become accepted that folks can make up any “facts” they want and others believe them without question.