Well by now I suspect that most readers have just learned to skip over this thread as it is probably a trifle boring to the normal PPrune.
Eyes in your backside refers to "excellent hindsight" rather than convincing forsight..
If you mean by experiencing a "far lower" failure rate, that the manufacturers were overly optomistic in their non-credible design assumptions used in the FMEA's I can agree with you in the reverser case. The problem was partly to do with lack of oversight of the many vendors' QA programs.
Regarding your comments on Service Buletins (SB) they are issued for a variety of reasons and in the case of the burner cans it was more for the rectification of shortfalls in presumed maintenance than it was to correct design defficiencies.
And as the person responsible for developing the rules by which system safety progresses forward by incorporating "lessons learned" I can tell you that time and money do not enter into the equations once the rule is promulgated.