Centering common lyrics vertically

[Hannes Kuhnert]

I have lyrics in two staves and also common lyrics for both staves and I’d 
like to have that common lyrics vertically centered. I don’t know yet how to 
do that. It would be easy if the number of staves was odd …

I haven’t found anything suitable in the snippet directory, but I have two 
ideas for getting it done:

• One could use a third lyrics context for the common lyrics and get that 
context in the right position.

• One could put the common lyrics in one of the staves and move that parts a 
bit up or down to get it centered.

Can anyone tell my how to do that or something different to get the lyrics 
centered?

TIA

Hannes Kuhnert