Tango fare is really only for the intra-canadian flights, where LCC competition is forcing AC to offer a cheaper price. The miles are non Q.

Tango Plus is competiting with the US based airlines, where you could fly UA or US and get full Q miles, AC had to offer a comparable product.

I know this will sound stupid, but Tango Plus was called "something else" but AC had to change the name to T+ because the "something else" was already used by another airline. Could someone remind me of that name please?