Re: undo custom delete

[rgb]

> undo... normally if you type a word in emacs and then delete it, one
> letter at a time (using the normal delete command), one utterance of
> "C-x u" will return the whole word. However, with this custom command,
> the letters are returned one at a time.

I, for one, was unable to recreate either symptom you describe.
After using backward-delete-char-untabify in the normal way, on
my machine, the undo key returned each character I deleted one
at a time.  In situations where fancy-backspace deleted more
than one character in a single keystroke, undo returned all the
deleted characters in a single invocation.  So it seems to work
as I would expect already.
Perhaps what you are calling "(using the normal delete command)"
uses some other command besides backward-delete-char-untabify.
If so, perhaps replacing backward-delete-char-untabify with your
"normal delete command" will yield the results you expect.