Re: Calendar, diary, and diary-mode

[Richard M. Stallman]

    There are at least two functions that do basically
    (find-file-noselect (diary-check-diary-file) t).  It might be a
    good idea to refactor this, creating a function that returns the
    buffer for the diary file, setting major-mode, etc. when opening.

That might not be a bad change.  But if there's nothing broken here,
I'd rather we leave well enough alone, and focus our attention on
other areas where changes would produce real benefit.
Have you looked at etc/TODO?