curioustoddler - 7:52 am on Jul 1, 2010 (gmt 0)
I have one experience to share. One of my friends was trying to rank well in a very competitive trade. Site was always ranking on second or third page for most keywords, but very few first page rankings. Then he tried to copy the top ranking site in trade. They had put all the deep internal pages in noindex, nofollow and their links on other pages in nofollow. I tried to stop him because i had the impression that losing thousands of indexed pages will harm his site. He went ahead with the changes and within two months his site is doing very well.