Well, I don't think anything can force the programmer to keep the prose and code in sync. The best we can do is give you an incentive to do so. The argument that was presented is that comments will get out of sync with code, but we're trying to provide tooling that will incentivize you to keep code and comments in sync.
I'd also like to say that if code is easier to read in the first place, there will be more eyes on it, and discrepancies will be resolved sooner. In most programming environments, a comment might describe a part of a much larger function. But the output of this code is far removed from the actual source. So discrepancies between comment and source are harder to spot.
It Eve, we intend these documents to be for more than just programmers. Who again, might not understand your code, but would understand the written prose and see the output /right there in the code/ that contradicts it. A bug like this would be brought to your attention much sooner than if your code was simply hosted as on GitHub.