- I can find no wording that says CANADIAN AMEX car insurance is secondary. For US-issued cards, the basic coverage is secondary and they have optional primary insurance at additional cost.

- With Visa (most if not all Canadian Visa cards, including Aerogold) coverage, drivers authorized by the renter are also covered for LDW/CDW, even though such drivers are not authorized by the rental company (for example you did not pay additional driver's fee). These drivers must of course have their own 3rd party liability insurance in order to drive the rental car legally.