Sigh. The TCK is one of the main reasons why Apache its resigning, and clearly that *is* what I am complaining about. That is the whole point. Despite of being licensed under GPL by its owner, Java cannot be considered free, because that same owner will prosecute you if you tried to implement it independently.
About the ability to revoke GPL retroactively. Unfortunately your optimistic unsupported assertion that such fear has no merit is not enough on its own. Just because we want something doesn't make it true. I have linked to pretty solid legal arguments that would have to be refuted by reasonable counter-arguments.
I have even seen Eben Moglen implicitly confirming this, though I think that link is dead now unfortunately.