How do 'sketches' work?

[jowcol]

I read that Koechlin would start by sketching the rhythms and meters first for a work, which strikes me as  bizarre.

[greg]

Here's what sketches look like; they are fragments, ideas, bits and pieces that eventually are worked into a cohesive whole:

http://www.pedro-amaral.eu/works/subpages/works02n1M.htm

This page contains more info about the work:

http://www.pedro-amaral.eu/works/subpages/works02n1.htm

Wow! That's a really interesting sound! 

[jochanaan]

I read that Koechlin would start by sketching the rhythms and meters first for a work, which strikes me as  bizarre.

Not bizarre at all if you're dealing with complex rhythms...or if the work is driven by rhythm...