My destination guides were absolutely slaughtered by algo changes dating back to Penguin ver 1. (No manual penalties)
Both MC and John Mueller, if my memory is correct, have stated that Disavow lists can be submitted for sites in this situation.
The things I am uncertain about are:
1) Is there any way of knowing if Google has actioned a disavow list (submitted approx 2 months ago)?
2) If they have, can I assume that any changes have already flowed through to the indexing of the affected site?.. or
3) Will nothing change until Penguin ver 3 is run?
Any experiences to share?