"Once-removed" bowling attempts may well exist. I guess that since the vast majority of sites that we monitor don't get down-drafted, there is little need for us to hunt this issue down and worry about it.

My main point is that just doing the right thing, continuously, over a long period of time, is the best defense against all of this. It takes commitment, patience, and resources.

I think you were saying the same with your "authority" statements. I agree.

Sites that race to the top of the SERPs based on unstable foundations seem to be vulnerable, for a lot of reasons.