I've recently come on board at a company to help with internet marketing. The bloggers have been posting almost identical content to two related sites with different domains that point back to each other. This practice, I've read, is known to invite Google penalization. But is there any way to prove that either site has been penalized? I'm not yet credible enough as an internet guy to simply make a statement to get things to change. I need data.
Having a history of keyword rankings would be ideal, but I do not have that.