I knew that the federal government was overstating the deficit before and would come in with a much lower actual number.  This was further helped by economic growth.  It's a classic underpromise and overdeliver paradigm that many businesses also do.   Some would call that being cautious but it also part of the long game this government plays. 

For I think the news next year will be even better, and barring some disaster by election time 2019 we will be back to a balanced budget.  Few voters will care about what the deficit promises from 2015 were when the government has a balanced budget to show, rather than the huge deficits they once "predicted". 

By unquestioningly swallowing the line about the deficits that the government fed them, the Tories did themselves a disservice.  They ought also to have been considering whether the deficit projected was really going to be the case and whether they were setting themselves up to be sandbagged.