Uhhh. No. Just no. I don't think you understand the meaning of "clean room" in this context. In this context, clean room means that the person in the room is untainted by any copyrighted information full stop.

The problem I'm describing is that in this case the kind of thing you'd typically want to write in that documentation is exactly the signatures of methods, which would amount to copying the copyrighted material and would taint the whole clean room. I'm trying to think of a way you could even do clean room engineering if the signatures of methods are copyright information. The reimplement from usage examples is the only thing I can come up with.

These $9 Billion dollars will look great on Oracles bottom line. The mega-billions in possible lost trade and efficiency make me think this ruling gets reversed with a vengeance.