TechWhirl (TECHWR-L) is a resource for technical writing and technical communications professionals of all experience levels and in all industries to share their experiences and acquire information.
For two decades, technical communicators have turned to TechWhirl to ask and answer questions about the always-changing world of technical communications, such as tools, skills, career paths, methodologies, and emerging industries. The TechWhirl Archives and magazine, created for, by and about technical writers, offer a wealth of knowledge to everyone with an interest in any aspect of technical communications.
In my experience, single source docs are more holy grail than reality --
technically possible, but enormously difficult to set up and manage.
When multiple formats are requested, I prefer to write the Help first.
The format usually provides me with "chunks" of information I can
recycle for a more linear document (print or .pdf).