One pays the same tax whether the ticket is booked with Aeroplan, United, Continental, etc miles.

The only difference is that if using Aeroplan points, you will be charged a surcharge when using Air Canada - this is not a tax. It is not government imposed. It goes directly to Aeroplan/Air Canada
No surcharge applies for booking on partners.


For shorthaul it may be a wash 15k vs 25k to save $100 - yeah I d spend less points too.

But if booking to Europe, and slapped with $622 extra - yeah I am going on a partner.