So you're saying whether a CLA requires copyright assignment or not is not important since it makes no practical difference? Sounds odd, it must make some difference.
No, it makes no practical difference. As I point out in my essay on the subject linked in the article, the problem with all CLAs is that they anoint one member of a community with broad rights to the whole work that no other member enjoys. The inequality that creates is the toxin. It makes no difference how the inequality is administered, whether by giving the copyright away to them (assignment) or granting them a license that conveys rights equivalent to ownership. They are then free to work on the code outside the community, make deals around it without including the community and generally violate the transparency principle. I've covered that in an essay too.
You also suggest that you can give permission to re-licence without assigning copyright. I didn't think that was possible.
Yes, the license these agreements use is broad enough to permit the recipient to relicense under any arrangement they like. That's the whole point in most cases.
Google's CLA seems fairly harmless, perhaps I'm missing something.
Clause 2 of the agreement you point to grants Google "a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license" - that's enough to allow them to do anythign at all they want with your contribution, including distributing it under a proprietary license in another work without advising you. If that's no problem to you then yes, it's just as harmless as all other CLAs.
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