They should have had either a smaller scope / simpler extension to IPv4 with a better backwards compat story for IPv6 only clients (some have since shown up a b

They should have had either a smaller scope / simpler extension to IPv4 with a better backwards compat story for IPv6 only clients (some have since shown up a bit). Or really done the reinvent - there were some interesting ideas especially for folks with lots of link handoffs (ie cell phones driving down a road etc) - can't find the write-up quickly.