Just realised: the National Service thing is a classic dead cat manoevre: when "the facts are overwhelmingly against you", nuke the conversation by throwing a dead cat on the dining room table. (Sadly, methinks the tale of the expression's Australian origins is another of de Pfeffel's straight-banana stories. Personally, I can't wait for this particular dead cat to become a reverse ferret.)

Meanwhile, I have a suspicion I know the real story that they were trying to divert attention from: Johnnie Mercer, the veterans minister, was shoulder-surfed while doing parliamentary business on a train, and the contents were leaked by the Times. Amongst other things:

His [Mercer's] memo states that he was upset that his attempts to let military veterans, who had previously been turned away from polling stations, use their ID cards to prove their identity when voting had been denied. Downing Street special advisers apparently blocked these proposals because it could also "open the floodgates" and allow students to also use their ID cards too.

This tale has only, to the best of my knowledge, propagated as far as The Register, and in particular not as far as the TV news. Dead cat managed; the fact that the Forces are implicated is a neat twist, as it shuts Mercer up too.