Xenaphon looks to have been briefed on what to ask and the fact defence appears unable to answer correctly, even though the information is available in the public domain, suggests they have been given an official answer to repeat. The question was on notice so, considering the politically sensitive nature of the topic, would have, as a minimum, been vetted by the ministers office, if not PM&C, or even the PMs office.
This whole discussion appears to be being controlled to the nth degree with a particular outcome in sight, first ASC, now the RAN and DMO looking awkward, wooden and uninformed. These are smart people but they are coming across as anything but, I personally suspect because they have been given a script to read and have been made aware of the consequences if they divert from it.