They had probably ignored the problems caused by this bit of desperation because they were busy wrestling with some of the other issues of single-sourcing, like the vastly smaller information bandwidth available in online help. It's led other writers to argue that the usefulness of online help is severely limited, and that we should think about writing more books. Both arguments have a grain of truth, but they also reflect plain and simple frustration resulting from the current-day avalanche of bad help. In fact, technical communicators who don't implement a single-sourcing strategy often become so resentful at having to maintain separate copies of similar content that they allow their help files and manuals to atrophy. Though they may have new ideas about how to improve explanations or organization, the tedious editing job involved makes even the hardiest soul reluctant to make a change.
Help systems belong to the family of application support.
A book may be the perfect teaching instrument, but context-sensitive help is unmatched for presenting timely information. It beats any paper-based reference for helping users sort out a problem or answer a question while using a program they already understand. Below I indicate some principles that can help keep things straight. These tips assume that you are starting with printed documentation first, and then converting it to a help format. For many reasons, including the fact that help has a much looser structure than print, this is usually the best approach.