WYSISYG (What you see if what you get) is the hallmark of a good authoring and publishing tool. Publishing process is the last stage of any technical communication project. Having a WYSIWYG tool, whether you are authoring for Print, PDF or HTML, enables you to preview the expected output as you develop the content and reduces surprises in the end. Surprises during the publishing stage are often the reason for project delays and nightmare for all project members.
In XML or HTML environments, style and content are separate. For example, while authoring XML documents in FrameMaker, the styles are applied through a template. Similarly, in RoboHelp, while authoring HTML content, formatting information is provided by a CSS. Both the tools provide an ability to choose different authoring and publishing templates. You can replace your CSS or template at any time during authoring or publishing.
I have often found the argument about WYSIWOO (What you see is one option) very hard to understand. If you are publishing for two channels, you can use two templates to preview the final output (WYSIWYG view for two channels). In any case, you need these two templates for publishing, why not share these templates with the authors.
With Adobe Technical Communication Suite, you can live link FrameMaker files (structured or unstructured) in RoboHelp project. That is content authored in FrameMaker is always updated in RoboHelp. You, therefore, get WYSIWYG not just for print but also for web output. If you can get WYSIWYG for both print and HTML and synchronized content, isn’t WYSIWOO an argument in favor of poor authoring experience.