one thing that can be done when the transition is made. we could make an initial switch of all IPv6-capable machines for a short initial period that would reve

one thing that can be done when the transition is made. we could make an initial switch of all IPv6-capable machines for a short initial period that would reveal all machines not capable, then switch back to IPv4 for enough time to get those now very aware of their problem. We could do that for several weekends prior to the real switch. Such an approach would require a lot of software to be changed, to be sure. But it might be worth it.