Chords with "optional" notes

[Alberto Simões]

Hello

There are musics where chords have a smaller note, that is optional.

I found some logs from this mailing list in 2007, suggesting things like:

           \tweak #'font-size #-4 g

Is there any easier way? (as in, less verbose).

In fact, I have a bunch of octave chords, where the upper note is 
smaller. If someone knowing a little of scheme would help me writing a 
macro/function for that, I would be much appreciated.

Best,
Alberto