Crossing over at one point is not as effective as an even crossover, since it is actually equivalent to an even crossover with one static and one dynamic point. Thus, building blocks in the middle are more likely to be disrupted than building blocks on the ends.

That being said, his approach is also a viable GA operator. It is called a uniform crossover. But really, to qualify as a GA, his solution only needs some kind of variation, mutation, and selection.