> Thanks. IMO that's worth a minor-mode like wdired.
>
> That would reduce needed keystrokes towards two - while marking
comments already may cost severals.
I've never used it, but you might be looking for poporg. From their doc:
poporg is a small Emacs Lisp project to help editing program strings
and comments using Org mode (or any other major mode). This can be
useful as it is often more convenient to edit large pieces of text,
like Emacs Lisp or Python docstrings, in an org-mode buffer instead of
in a comment or a string.