Air Canada was not making any money before the restructuring that just took place. Tango was launched as a discount brand scaled down AC version if you will. It's purpose was to get some market share back and It was going to be shut down by the competition bureau but after C3 shut down they figured what was the point then. While it was cheaper to run there was no way that they could compete with any other companies front and back end salaries.
That is a fact. So all AC could really do at the time was to lose less. Look it up if you like.
I am glad we are still hot on the topic.