I still think its a stretch to lump in systemd and upstart into this argument. I think the difference of opinion there is primarily one of technical design not the politics of copyright. The assignment issues around upstart may have complicated things and kept people from communicating, but I'm not sure removing the assignment policy would have changed the course of events. At least that is my reading of things.
I think it weakens the argument you are making to include them as examples, unless you can point to some sort of previous discussion in the context of upstart development where good-faith contributions from contributors were turned aside by the assignment policy requirement. I'm not aware of that ever happening.
I think what is happening right now with LibreOffice stands up by itself as an unfolding relevant case study to make the point.
Though I would like to see if the clutter development experience has something interesting to add. When clutter dropped its assignment policy did contributor activity rise in a noticable way?
A certain individual has argued in private with me that business entities,such as the one that previously required assignment to clutter, only drop the assignment requirements after they are no longer incentivised to lead the development. Essentially the argument made to me was that dropping assignment is a "we wash our hands of it..throw it over the wall..and let the community have the scraps" action on the part of most business entities. Pardon me from interpretatively paraphrasing from a private conversation. I did have the foresight to obtained permission to archive and republish the short conversation. You can read the argument in the context of the conversation from Sept, 2010 here: http://jspaleta.fedorapeople.org/A_conversation_with_Mark...
I don't think opinions on the matter have changed. The people who walked into the Harmony discussion in favor of for-profit assignment still feel that way. The people who came in against it, still feel that way.
Nor do I think Harmony as drafted are going to change the character of the dispute. Harmony is a codification of the battlelines. I know some people are _hopeful_ that some for-profit entities who switch from in-house contributor agreements to Harmony drafted agreements will be choosing more contributor friendly options. But I don't see any evidence of that. And I don't plan to give any for-profit entity the benefit of the doubt on that score. Whether you choose a Harmony statement or not is not important. It is the specific choice and the details that matter. I don't plan to pat any entity on the back for choosing a Harmony option that requires assignment to a for-profit with sufficient promisebacks to protect the long term interests of the uncompensated contributor.
The Harmony drafts allow for pretty much all the bad for-profit behaviour that is currently allowed now. At best Harmony will make it easier to identify. At worst Harmony will give for-profits political cover that they can hide behind when their choose unfair/unbalanced assignment policies instead of the more reasonable Harmony options.