showing MultiRests when both instruments have rests in Frenched score

[Paul Scott]

In a simple Frenched score for many typical instruments often all (both) 
parts have rests.  Using RemoveEmptyStaves removes the staff the 
multi-rests and only leaves rehearsal marks.  How can I cause the staves 
and multi-rests to be engraved? 

If the following is the solution where can I put showMultiRests so that 
it doesn't override RemoveEmptyStaves and show staves whether they are 
both empty or not?

http://lsr.dsi.unimi.it/LSR/Item?id=312

TIA,

Paul Scott