Flatten TOC on device transfer?

[silentguy]

Hi!
while I was thinking about new features for my device plugin, I had an idea that would probably be better suited for the metadata plugboard or something so I wanted to propose it here:
My ebook reader only supports one level in the TOC of epub files, and this leades to him only using the highest entries and ignoring all the others. This can be quite annoying because I have a few books where the highest entry are just one or two nodes called "Part 1/2" and "Part 2/2" etc. Therefore it would be nice to have the ability to tell calibre to flatten the toc upon transfering the book. Either in a simple "pull all entries to the same level" or with a certain degree of granularity, like "Pull up first x levels" or "Pull up while 'few' entries" etc