Since the birth of MediaWiki, even adding a new comment on a Talk page opens a vast:
<textarea id="wpTextbox1" cols="80" rows="25" ...
Which the user must then scroll past to finally get to the
'Save changes Show preview Show changes Cancel'
line, after entering his line or two of text.

Let's face it, most edits are not a wonderful creation of a whole new page, but instead just at the most adding a few lines to something.

And in all cases there is already a extender /// mark to pull on in the corner anyway.