The slightly more challenging issue is just to determine which NIC is more heavily loaded. So it requires cross-NIC monitoring, similarly to what we presently do for cross-channel download performance monitoring. Given a balanced distribution of work across thread pool-associated NICs, we should be able to run them in parallel and get most of the expected cumulative benefit. This is basically running a load balanced internally. This can be applied externally as well, but the OS doesn't do this.