SQL can bite back with the sometimes non-intuitive consequences of its version of three-valued logic. Unfortunately, some professional programmers have trouble with it. I once had to sort out a situation where the developers were blaming the users for not using the system correctly, when the problem was with the queries.

Spreadsheets are another good counter-example to the author's thesis. They, too, can be misused, but that is outweighed by the great many cases where they are used well by non-programmers.