Thanks.
Okay, so it almost sounds like the problem here is Congress is reticent to dig into surveillance issues, not because they can't keep the proceedings secret during a hearing on classified matters, but because passing legislation that responds to issues uncovered during such a hearing would have the undesirable effect of promulgating exactly what potentially problematic issues are at play in the text of laws (which would then have the undesired effect of notifying legitimate enemies/adversaries/targets as to what the specific technical capabilities of NSA, et al., are). So, if this is somewhat accurate as assessment, the congressional response is to then create a legal gatekeeper that can adequately assess the sensitive nature of the issues and (hopefully) provide sane guidance and oversight without codifying problems in laws. Hence, the prevalence of rules and policies that allegedly safeguard citizens, but no specifically detailed laws on the matter?
Now, the task appears to be interrogating whether or not this is a valid protection of the citizens' rights without violating or unintentionally weakening the Executive powers we depend on for national security, right? Given that the leaks have publicized an alleged extent of sigint activities and capabilities, at what point does Congress act to legislate legitimate safeguards?
[edit: a bit more clarity]