Agreed that it should work, but I'd prefer to enable and configure failover behavior in ESXi rather than UCS. In my research on this issue, I found a thread over on the Cisco UCS forum that has a clear statement regarding this configuration: https://supportforums.cisco.com/thread/2187653.
"Never use fabric failover with a hypervisor vswitch. Let the failover mechanism of the vSwitch handle the network outage."
So while it may be a valid design, it looks like the consensus is to let your vSwitch handle the failover.
mike