[AaronBBrown]

It does, but it's not very useful, as you cannot have a VIP span multiple AZs and typically a spontaneous instance failure is correlated with an AZ problem. ENIs (and IPs) are tied to a subnet, which is tied to an AZ. Even the example only utilizes a single availability zone. While there may be a tiny bit of additional redundancy added by doing this, you still need a way to fail over to another availability zone.