The mere act of having to ask for a licence already has a chilling effect, and the legal uncertainty just makes it worse. For example, if Google ever gets into

The mere act of having to ask for a licence already has a chilling effect, and the legal uncertainty just makes it worse. For example, if Google ever gets into a patent war with Microsoft, would their 'free' licence be revoked? Does that mean the moment they'd use this coding they risk having their own patent portofolio be unenforceable? If so, they would have an interest in not using the technology from the 'free' licence, and software would be set back.