How to unfold percent but not volta repeats?

[vampyrebat]

Hello, I'm having an issue with repeats in MIDI output. This is for a score of 
multiple voices, where musicians who will be playing the piece will use the 
MIDI as a learning aid.

I don't want volta repeats included in the MIDI. Hearing the same passage 
played twice serves no purpose to musicians learning the piece.

However, I *do* want percent repeats included. These are just a notational 
shorthand in certain voices; the measures they represent are still part of the 
harmonic structure of the piece. For MIDI learning purposes, passages with 
these measures omitted will sound wrong.

As far as I can tell, \unfoldRepeats is all-or-nothing. Am I overlooking a 
simple solution? (I sure don't want to have to wrap chunks of my source code in 
tags to be selected based on whether output is PDF or MIDI. This creates a 
maintenance burden, as then simple changes need to be made in multiple 
places--usually a sign of badly written code.) Any ideas appreciated.