I used to put a lot of faith in the outbound link pattern of a PBN site being what would ultimately de-cloak the network after all other precautions being taken. In a perfect world, outbound links are effectively a site's fingerprint, almost unique to it and arguably statistically unlikely to occur identically again naturally. In a perfect world for Google it seems almost like it would be almost easy to identify sites that cross a similarity threshold and then inspect them closer, after all they have everyones 'fingerprints' on file for inspection but it's not a perfect world. Having scraped for expired domains for some time now, I'm not sure sure it's actually that effective path for Google to go down. In fact, it's such a glaringly obvious approach for them to take that it makes me think, why aren't they already doing it and taking out people's networks overnight? I believe the answer lies in the collateral that would be taken down. I'm aware Google has never shied away from catching some innocent sites in their net if it will cripple the Black Hat world enough. However, having seen the messy world of links out there on regular sites with link pages, charities, clubs, societies, universities, shops, industry leaders all interlinking and creating these 'fingerprints' too, it doesn't seem such an obvious course of action for Google to take. With all Black Hat activities that aren't churn and burn, the objective is blending in with the herd sufficiently as to not create algorithmic suspicion. I'm still under the opinion that an identical site fingerprint is mightily suspicious but this can be relatively easily overcome by linking out to other sites from within our posts. I would be interested to know what other people think.