No it does not. Some creeps through the registration system, which is why we have additional trust measures afterwards.

On my own site I see 1 or 2 spam posts a week although I get the feeling it’s real people doing the registration. They sign up, make 1 comment, get reported very quickly, then banned.

We haven’t had to make our signup/registration system that strong in of itself though, because most of our largest clients end up using some SSO method exclusively and will have their own prevention methods.