[rdl]

There are so many levels of "TOP SECRET" (channels, SAPs and other restrictive markings). TOP SECRET is essentially the beginning of "actually important" (and I believe there is even plenty of SECRET stuff with restrictive markings which is thus more sensitive in practice than generic TS; some of the restricted markings are in US Code explicitly and pre-date the C/S/TS system). The "SI" part of TOP SECRET/SI was probably more significant. The presentation itself wasn't hugely sensitive (somewhat informed speculation -- at least based on the parts which were published, and a generally informed but not specifically informed review). No specific collection techniques, etc.