\paper vs \layout

[David Bobroff]

I'm a bit puzzled about how to go about something.  A \paper block can 
contain a number of things influencing vertical spacing.  A \layout 
block can contain some of the same things that a \paper block can 
contain (unless I'm mistaken).  While \paper blocks influence the entire 
document a \layout block influences only its containing \score block 
(correct)?

My current problem is that I'm making a transposition of an existing 
etude book for myself.  I'm trying to contain it all in a \book block 
but I want to add \layout (or \paper) blocks to each \score block, where 
necessary, in order to get the practical layout/page turns in the 
original.  I could do it with explicit \breaks and \pageBreaks but this 
strikes me as inelegant and kludgy.

With some experimentation I found that the useful controls:

page-breaking-between-system-padding
between-system-padding

...seem to do nothing when contained in a \layout block, but work when 
contained in a \paper block.

I've been trying to find some reference in the docs about about either:

A) Using such spacing commands with a \layout block or

B) Using (or discarding) a \book block while using \paper blocks with 
each \score block.

It is my current understanding that the last \paper block in a *.ly file 
will be the one used and any previous ones will be disregarded.

In short, I would like to have all of the essential musical information 
in one file and another file which \includes that file and sets it all 
up in a sequence of \score{} blocks with any necessary tweaks for each 
\score{} that will satisfy the page turns, etc.

-David