I think this is similar to the security concerns that surround Open Source software. Sure, proprietary companies keep their source a secret, but when it's open source, the community can push out a fix instead of waiting for the company to do it. Not to mention everyone can improve upon it.
Yep, everyone can improve upon it
including the perpetrator!
But that's the same for forensic science. A perpetrator could spend years studying police investigation methods in order to fool them or evade detection and they may well be successful, but the other 99.99% of perpetrators won't spend years studying this, and will get caught out.
Likewise, the publishing of every known sockpuppetry detection method would only affect the minority of puppet masters that choose to study first and become experts at fooling the algorithms. I'm guessing that would be a very small minority as most wouldn't take the time to do this.
