[ra]

Sure, I don't disagree with what you are saying. However I think that the way Amazon presents the concept of an AZ is that it IS isolated from other AZ's in the same region.

Even the name, 'Availability Zone' implies that it is isolated from other 'Availability Zones' in the same region. And that text I quoted does nothing but substantiate that inference.

I just think that Amazon are misleading here. Maybe they shouldn't call it an Availability Zone.