The desperation continues
If it is the first case, that the Tories have nothing good to say about themselves, the implication would be that they Tories have a hidden agenda. That they don't want to tell people about their agenda would imply that what they do have wouldn't resonate with a majority of Canadians and thus would cost them at the polls. If this is indeed the case, then Canadians need to worry about the integrity of Harper and his party. By hiding their true intentions, the Conservatives are basically lying with their actions. They are telling the Canadian people "look, we're moderates" in order to win votes and absolute power. Once that powere is in hand, the Tories would then revert to their more theo and neo-conservative roots and push through policy and legislation that would anger the voter.
If it is the second case, then we really need to get rid of this "government" and soon. If the Tories have basically run out of ideas to the point where the only way they can get more standing in the polls is to attack the opposition, then they don't deserve to be government. This case would make it seem that the Tories are so insecure about their own, very short record in government, that they won't hold it up to public scrutiny lest it cost votes. It is safer in this instance to attack the opposition in the hopes that no one will notice the lackluster performance of the Tories since they've been in office. This is made even worse by the perception that the Tories have run completely out of ideas and the attack ads are to divert attention from this too.
The truth is probably a bit of both cases. There are aspects of what Harper and his party would like to do that would be unpalatable to the majority of Canadian voters. Since it would be difficult to get such legislation through the house and no government wants to fight an election on something unpopular, the Tories need to divert attention from the inaction that this generates. Combine this with the fact that Harper and the Tories have run out of ideas and it becomes clear that they have to run attack ads, as there are no other kinds of ads that they could run. Any attempt at ads that try to build up the Tories are doomed from the outset since their record is abysmal, much of what they want is unpalatable which leaves nothing to brag about.
So it is possible that we are seeing the Tories now thrashing about in the water as the good ship Harptanic slowly slides under the waves of popularity. Only a sudden change in attitude and direction will save this party in the polls in the next election.