If a comment needs to be amended, how can we edit it? There seems to be no Edit option.
Where is the link to change text?
Just after you've posted a comment, if you hover over the comment text you should see something like this:
Click 'edit', and you should get the original comment input UI back.
Comments are only editable for 5 minutes, after which the "Edit" option is removed.
See this previous thread on the main SE meta board as to why this is.