Nice to have - manage differing number of syllables in verses, choir etc.

[Esa Erola]

Hi,

For a chosen verse in multi-verse choir etc. sould there be any chances with 
reasonable enough effort to create a command to be used inside lyrics to skip 
once a slur

There is a nice snippet do to this, just a bit hard to use in multi voice 
choir.

It would be nice to include before a syllable something along the 
lines "...this \once \skip \slur nice cat..." ( while the other verse would 
have "... that yel -- low dog..."  - one more syllable )

the snippet:
http://lsr.dsi.unimi.it/LSR/Item?id=308

Thanks!
br
esa