It has come as a shock to me on more than one occasion
that certain sections of PM behave a little differently
from others with respect to the "Preview" mode. You
hit submit, a little prematurely perhaps, but think nothing
of it, until you can't find a way to edit your posting
short of pestering a Saint.
If you are replying to a message, for instance, pressing
"Submit" isn't really all that dangerous because you can
always edit your posting later. However, if you submit
something to a section directly,
there is no going back
unless you get some help from the editors.
It would be handy to include some sort of note below the
buttons that indicate if this is a "Submit, but don't worry
you can change it later" button, or a "Submit, and you
better be darned sure about it" button.
This
node, for example, cannot be edited by me directly.
Of course, if you know a bit about
Everything
you can always kick it into "Edit" mode for your node, but this
seems a bit crazy.