I have slightly edited and reformatted the replies I received to this question. I'll keep the replies online for about a month. I recommend it highly if you want a cognitive psychology viewpoint on the issues. I received a thesis paper and other material from Robert Fenchel describing SARA, the System ARchitect's Assistant. It is a tool for building consistent user interface, with prompting similar to the TOPS-20 cmnd jsys, but going way beyond that.
Semantic help is also available, as well as a way to create documentation from it.
This is not online in the summary. It is included in the summary file. Interface design seems to be a field unto itself. There are journals devoted to the subject that go into tremendous detail about the most extraordinary things. If you want detailed info on a particular aspect there is a wealth of stuff waiting at your CS oriented library.