I have one last little point.
The caretaker provision is applied to a government that does exist. It does not dissolve with Parliament. There is still a need, in case there is a war or a national emergency, to have certain powers available to deal with extrageneous or natural disasters as they come. However, the parliamentary budget office is under Parliament. If Parliament itself is dissolved, I just can't see why we would want to have one element of Parliament that is not like the rest of it. To me, that's not a great choice.