Regular_Joe - 6:43 am on May 22, 2012 (gmt 0)
I didn't read the whole thread, because I'm going to bed, but I going to drop this in here anyway...
When I look back over the last year and a half, my site was on the front page of Google, pretty much in the same position for the whole time, but I keep getting stepped throttles to my searches, just like I'm having little penalties added step by step. Each one takes a little bite out of traffic, with bigger bites now and again, like in October and April.
My thoughts are that as you fix parts of your site, you should see the little bites drop off within 30 days or so, and then see the big bites drop off in 3-12 months, depending on what the penalties are. Things like broken links and too many 404 pages should fall off pretty fast, while stuff like links farms and keyword stuffing will take longer.
As an example, I killed a link farm/link ring I'd built in early 2003 or 2004. Exactly 6 months to the day after I took it down, the site they were linking to popped back up on the front page, in it's old position. The site was killed on July 15th 2005, and just popped back up 4 years later, after I killed the farm. (I killed the farm in a couple of hours, by deleting the sites and parking them.)
My point being, get rid of the 404's, fix the spelling errors, remove all the dead links, check the code and make sure it's clean. Then, start on fixing the keyword density, the 50,000 spam p**n links that your competitor tossed your way from a $5 website I can't mention here, and make your content thick and rich. After a year or two, your site should come back... (Just about the time the bank forecloses. LOL)
I'm rambling... See, I told you I should be in bed.