Robert_Charlton - 9:19 pm on Jan 21, 2013 (gmt 0)
So you'd in essence like to redirect only to preserve historical traffic and get visitors to the newly branded domain. I assume that to accomplish this, you'll have to go through the disavow process on the unhealthy domain before 301ing.
If you did a 301 under present circumstances, the tainted backlink profile would follow the 301s. There's currently no such thing as a "nofollow" 301 or equivalent... and, since it's likely that your old index page is tainted too, you couldn't selectively 301 untainted pages.
I suggest that you get as many links physically removed as possible, then disavow other likely offenders. As your goal is not to retain link juice to the old domain, but just to get the domain clean and to retain good traffic, I'd prune all links that are unlikely traffic sources and disavow more than necessary,
Once the disavow request is accepted, I assume that you could safely 301 the old domain. I would not do it before.
This approach is conjecture, as I haven't yet heard of anyone doing it... but I'm seeing other sites floundering in similar situations, and it's the only approach so far that makes sense to me.