I think it's more conscious than how you describe. I agree that progressives are looking through it and waiting for a 'signal' or proof of what side he's on. The way you described it is the same I see it. They don't feel comfortable laughing until they get a sort of token nod. I think he's purposely NOT sending that signal or token nod. There's something about his special and snl episode that almost feels like a dare.

I couldn't help but imagine a conference call between Rock, chappelle and Louis. I'd bet Rock's next special is gonna continue the same pattern and probably up the ante.