Hello,

the Open Document Format specification allow documentes to be stored/transmitted as a single XML document (flat) instead of as a zipped collection of files (packaged).
This has many advantages as noted by Fridrich Strba at his talk this year at FISL: https://speakerdeck.com/fridrich/flat-odf-the-under-estimated-flavour-of-open-document
Inspired by this talk, I've made a patch to export Moodle Gradebook as a Flat ODS document.
This patch changes the way the ODS file is generated.
The code is much simpler, but the resulting files are expected to be bigger, because it is not "zipped" anymore. Also, because of this, the process is much faster and uses less resources from the server.

Hope you like,
Daniel