just a layout question for my curiosity

[Walt North]

I don't have a specific problem here but I'm curious about this 
behavior.  I believe understanding why things behave the way they do 
make for better end results.

So...  in the code below if I have two layout block at the global level 
they get merged and the result is what I expected.  But I put two layout 
blocks within a score it causes the lyrics to print twice. I did find 
that I can put the layout into a variable and that nest that variable 
inside another layout to get the behavior I want.  So now it's just 
curiosity question.

\version "2.24.4"

ly = \lyricmode { test2 lyrics }

\layout {
}
\layout {
}

\score {
  \layout {
  }
  \layout {
  }

  \new Lyrics \ly
}