To complete your quote, you may want to read this Aviation Week story. It seems that some operators ignored service safety bulletins from GE and GE then requested the NTSB and the FAA to issue these directives.
OK, I accept that the AD was issued for that reason, but it still remains that the failure mode was identified in the 1970s, and GE did not issue their safety bulletin until 28 August 2009, 14 months after the first noncontainment incident on 07 July 2008, and 5 months after the second on 26 March 2009.