klark0 - 1:07 pm on Nov 8, 2012 (gmt 0)
How about Pages with query parameters ? Mobile switches ? Print / Email ? Check for www, or no-www. Check for no-trailing slash or trailing slash - one should return 200, the other 301.
My approach has been to get rid of all that, or replace it with a solution that doesn't add to # of pages Googlebot has to crawl.
Currently I have 7,000 pages not selected. I trying to get it under 1,000 which is approximately how many pages that should be indexed. So far it's been dropping very slowly. Only about 100 pages per week over the last 8 weeks.