On the subject of unhelpful deponents, here's a reenactment of a real deposition.
One hopes it'd go better than that.
(Among other things, this is why you go in
very intensively prepared, with a ton of documents ready to refer to if necessary. TSA, like most of the government, has a bit of a fetish for having official documents with definitions of things. I'll be asking for those. For instance, what
is a "gel" anyway?)
(Also, incidentally, the deponent's lawyer is committing sanctionable conduct there by leading the witness, objecting in a manner outside of the set of permissible objections, having extended discussion instead of the witness, etc. He could get fined for that.)