claaarky - 9:00 pm on Aug 6, 2012 (gmt 0)
Personally, I think if you have noindexed low quality pages that are 1 click away from an indexed page, the indexed page will still suffer on the basis that if google sends traffic to the indexed page, the visitor can easily find your low quality content.
Google is trying to keep its users from low quality content so personally I don't think noindexing will help much. I think you need to remove low quality content or improve it for a quick (within 3 months) recovery. That assumes any pages you improve are actually improved in the users eyes. If you remove low quality content it's gone, problem solved. Improving pages risks prolonging the pain in my view, although if a page is getting traffic it makes sense to try to rescue it.
Sgt_kickaxe, I think you should trim off those other pages if they're bringing no traffic and you're certain they are the low quality pages that are causing your problems. I would only keep them if you think they could become high quality pages, but the longer they remain on your site in a condition your users dislike, the longer the pain will go on (in my opinion).