aakk9999 - 6:39 pm on Aug 4, 2013 (gmt 0)
If the aim is to redirect the direct traffic to a new site, but to avoid the penalty being forwarded, and the ranking of the old site in Google is not important (since the site is slapped with a penalty), then you could:
- block the old site completely with robots.txt
- wait until Google picked up the changed robots.txt (once blocked, check your logs to ensure Google is not requesting pages from your site, other than robots.txt itself)
- then implement a redirect from the old site to the new site
Planet13 made a very good point - unless you are also trying to preserve search traffic as well (since if you block the site via robots, the remainder of search traffic will disappear). If you are trying to preserve search traffic too, then I am wondering how much of the remaining 30% is the search traffic and how much are referrals and is it worth trying to preserve it?
If 70% of the traffic was direct BEFORE Panda and Penguin, I would seriously consider just keeping the old site.