Out of desperation, I did a 301 re-direct to a new domain, and it worked (mostly).
I went from ranking: 1, 2, 5, and 8 with my main keywords to currently 2, 3, 8 and 10. So not a full recovery, but I was pleased.
Fast-forward 5 months to today. I've been so scared of another penalty, and of "wasting" any PBN links, that I haven't built a single link to the new domain at all. I just assume that with the next Penguin refresh, the site will be hit again. But it's been 5 months, and I'm getting antsy.
My question is: would you bother doing any new PBN link-building to the new domain, to try to bump it up back to its old earnings/rankings? Or is it too risky / not worth it, once the Penguin refresh comes, so just leave it alone?