You've probably already thought of this, but I'll say it anyway just to get it in the thread: I'd recommend including in your discovery any and all communications, advertising, or decorative materials, both physical and electronic (including but not limited to, memoranda, notices, emails, directives, posted orders, pamphlets, leaflets, posters, wallpapers, screensavers, newsletters, etc) mentioning screening procedures related to liquids, gels, or aerosols; screening those with physical or mental disabilities; screening assistive devices; professional comportment/behavior/conduct while on duty; choice of/escalation of screening methodology for specific situations - from TSA, from the SFO FSD, from Covenant, and from the SFO airport authority itself.

You'll be buried under a mountain of materials, but part of your strategy should be to show how the hundred different cooks in the kitchen issue confusing and contradictory orders to the staff under them, many of which likely violate both TSA's stated policies and the actual law. TSA may issue a policy memorandum that says one thing, but if that is contradicted by a poster in the TSO break room, or an email blast sent by the FSD to all TSOs at one particular airport, you might only get the policy memorandum and not the poster.