As I already claimed several times, the Fred update is a general quality update targeted at overoptimized domains. One of the best working strategies seems to be, to reduce keyword density in general as well as keyword alt tags in special. Hereby I want to reinforce this claim, by showing the results from removing keyword alt tags and their influence of rating. This are 3 different pages on the same domain, targeting 3 different keywords. On 2 of them I removed the keyword alt tags and they got reindex within 2 days. While the third, without any changes stayed the same.