I don't think that's "begging the question". Google's corporate counsel determined current law allows for clean room reimplementation, so that's what they did.

I don't think that's "begging the question". Google's corporate counsel determined current law allows for clean room reimplementation, so that's what they did. This was subsequently challenged, and that's where we are now. This isn't a case of Natural Law where the decision is commonsensical -- it's up to the courts to make an evaluation based on other established caselaw (in this case copyright), and there's certainly room for interpretation.