Notation question - alternate endings without repeats

[Dieter]

Hi All,

I was giving my partner a hand with a little project using Lilypond the other 
day - setting some bagpipe finger exercises she wanted to pass on to some 
young pipers.  We found the the bagpipe.ly and Svenax's bagpipe_new.ly 
libraries very useful - thanks to the authors of these.

The place we came unstuck was that the exercise tune logically (or musically, 
really) ends with a finger movement a real beginner might not be proficient 
with.  The exercise should therefore have two alternate endings - the more 
"musical" one, and the simpler one that a real beginner could use in the early 
stages of their learning.

I assumed there might be something alog the lines of a volta bracket for this 
situation but on searching I could only ever see these discussed in the 
context of alternative endings for a repeated passage of music.

I've done some searching and have been unable to find standard notation for 
alternate bars not associated with repeats described anywhere - doesn't mean 
it doesn't exists of course.

Can anyone point me to how this might be notated in a "standard" way, if such 
exists, and also, how that representation may be produced in Lilypond.

Thanks in advance for your time.