Creating a stringHarmonic function

[Kieren MacMillan]

Hello, all!

I'm trying to come up with a Scheme function to generate string harmonics 
automatically.

I figured I'd do it in two steps:
    1. Create a function that takes a chord of three notes, and formats each 
note(head) appropriately.
    2. Modify the function to take one or two notes, and generate the other 
parts of the notation accordingly/conditionally.

I've started Phase 1 by trying to see how I would build it manually:
____________________________

\version "2.12.2"

originalMusic =
{
    1
    8
}

harmonicMusic =
{
    \once \override ParenthesesItem #'font-size = #-1
    1

    \once \override ParenthesesItem #'font-size = #-1
    8
}

\displayMusic { \originalMusic }
\displayMusic { \harmonicMusic }
____________________________

Questions:
1. Is this a good way to go about formatting the note(head)s?
2. Is #'duration-log the best way to force the sounding pitch to look like a 
quarter-note head, regardless of the chord's native duration? [Obviously the 
sounding pitch adjustment should have no effect on the timing of the chord.]
3. How can I turn off the stem of the sounding pitch? [n.b. I know I could put 
it in a separate Voice context, but I'd like to avoid that if possible.]

Thanks!
Kieren.