The same thing happens under the scrutiny of the FBI all of the time....the same oversights occur in the ATFE when repeat offenders end up buying guns 'legally' just because they slipped through the net. No system that I'm aware of is fail-safe or it wouldn't be in the news wth the regularity that it is. 
That is very true. The point, when looking at the BSA, is merely that what happened regarding the abuser gives the insurors a potential legal position to deny the claim and probably lends weight to the lawsuits that have led up to this point.
