Jim Hergert mentioned that aluminum "oxidizes very fast so you need to bond
it within 2 or 3 days to get full strength".

Jim, perhaps you made a typo. I presume you meant to say that aluminum
should be bonded within 2 or 3 HOURS of being etched.

In addition bond failure can occur when parts are etched but not  primed due
to corrosion attacking the highly active etched surfaces resulting in
subsequent peel failure.

I quite agree that a properly placed mechanical fastener can greatly reduce
the chance of a disbond due to peel failure.

Ted Stanley