partcombine and quote don't play well together

[Kieren MacMillan]

Hello all,

The snippet below contains a [M]WE showing how partcombine and quote don't play 
well together. This limitation is interfering with my ability to put together 
the Awesome Divisi Choral Framework™ I'm currently working on.

In <http://lists.gnu.org/archive/html/lilypond-user/2016-08/msg00215.html>, 
Malte offered a solution which helped me get through the same issue when I was 
cramming out an orchestral score. But, as Malte points out, the method is 
hacky, and has limitations, and ultimately

> it would be nice if LilyPond allowed quotes that really copy the quoted music 
> to the quoting instrument.

Is there a superior workaround?
In particular, is there a [long-term] fix/improvement we can easily and quickly 
get into the codebase?

Thanks,
Kieren.

%%%  SNIPPET BEGINS
\version "2.19.60"
\language "english"

sop = { c'8 r d'4 }
\addQuote #"sop" \sop

alt = \sop
altQ = {
  \quoteDuring #"sop" s2
}

\markup "Partcombine + variable = SUCCESS:"
\new Staff \partcombine \sop \alt

\markup "Partcombine + quoted = FAIL:"
\new Staff \partcombine \sop \altQ
%%%  SNIPPET ENDS
________________________________

Kieren MacMillan, composer
‣ website: www.kierenmacmillan.info
‣ email: address@hidden