Yes. That is the layout I was thinking of.
The reason we use two vMotion vmkernels is that this allows 2Gb of vMotion traffic throughput in total. If we only had one vMotion vmkernel then we would only be able to achieve 1Gb maximum throughput for vMotion events.
You can use a single VLAN and subnet for the vMotion vmkernels. But each host will have two vMotion IP addresses.
Cheers,
Paul