I think the bottom line is ... they're going to have to show us the bacon on this one. 7 years? Show us some bacon...classified or not they need to declassify it and tell us specifically how this has been successful. They can do that or explain specifically what it is they get....
If it is deidentified markers matched up to numbers, mined to fine some patter, then identified for those that pass the pattern, then analyzed and possibly get a warrant for it...I think (contrary to what a lot of us like to say) most Americans would be ok with this PROVIDED that they could certify those numbers that become identified (after passing a pattern) are very low AND that there are a number of terrorist activities that have been thwarted...
But the bottom line is we can't continue indefinitely condoning this without declassified information that allows us to consider it intelligently...