Hi Mike
I agree there appears to be a problem using the Originating Port ID or LBT teaming when both ports are connected to the same external switch. Our configuration currently has that as we are using one CISCO Nexus for the 10Gb connectivity. Our redundancy is at the Virtual Connect modules where we have standby 1Gb uplinks on each module should the 10Gb switch fail.
We have the Nexus switches with close to the latest firmware so I don't think it is a CISCO firmware problem .More something to do with the vSphere load balancing without using LACP on the same CISCO switch.
I will ask our network guys to move one of the 10Gb uplinks to a different Nexus and then see if this resolves the problem. We have an engineering test enclosure I can do this with.
Will get back to you with the results.