DOCBOOK: Purpose of the moreinfo attribute: is it required?

[Mike Broschinsky <mbroschi@das.state.ut.us>]

I am just beginning with DocBook, using Emacs and PSGML to author help documents. I have noticed that for a number of different elements, notably guibutton and guilabel for example, PSGML will automatically insert the moreinfo attribute with a value of "none".

My questions:

What is the function of the moreinfo attribute?

Is it required?

Lastly (and an app related question), if the attribute is not required, is there a way to tell PSGML to not insert it (maybe a better question for gnu.emacs.help, or the PSGML mailing list, but I thought I'd try here too)?

Thanks,

Mike