I guess my understanding of “detection, identification, analysis, prevention, investigation or disruption” is that they're trying to include every possible activity that at least the 17 recipient institutions engage in. Perhaps with the change to necessity and proportionality, there will be a bit more rigour here, but the outer reach, as I understand section 5, is really supposed to be defined by the enabling framework for each agency.
I think this goes back to what my colleague Professor Forcese said, which was that rather than trying to paper over and provide a one-size-fits-all solution in the act, in some cases it may be necessary to go back to the enabling statute. For example, if you believe—as I do—that the case has not been made for CSIS to have disruption powers, then that might influence how you would go about structuring that final clause in section 5.