I would think it highly likely that members of the UK armed forces are advised that, when taken captive, making statements of that kind is a perfectly acceptable, and indeed advisable, behaviour. It seems pretty normal practice in these kind of situations,anyway. Sometimes prisoners go in for coded ways of indicating they are putting on an act.

Confessions of this sort by captives are pretty evidently meaningless - as meaningless as guilty pleas by prisoners making plea bargains, like that Australian kid the other day who'd been banged up in Guantanamo Bay for years.