Turntable.fm co-founder Billy Chasen has torn into what he terms Facebook’s “cognitive dissonance with sharing” in a lengthy post on his blog discussing the contract between explicit (where the user chooses what to share) and implicit (automated and `frictionless’) sharing. “When we launched Turntable.fm, I drew the line in the sand that we would only have explicit actions,” he says. “I received a lot of pressure from some advisors that we should be as spammy as possible because it works. We grew fantastically well based simply on having a great idea and product and didn’t have to resort to it. Then, like many other startups, I bent that rule when Facebook introduced the custom open graph.” He adds that form this week, new Turntable users “need to turn on implicit Facebook sharing in their settings”. He says that this can services going this route can get “viewed as spammy and don’t need it if you build something great”. He offers a number of solutions for Facebook here, including making implicit actions “all go into a holding pen somewhere on the site where users can then publish the ones they want (thereby turning them explicit).” Read the full blog here.