Yeah - on one hand you would need to use this "quickly" to help with IPv4 exhaustion before it becomes irrelevant. On the other hand (as you said) trying this t

Yeah - on one hand you would need to use this "quickly" to help with IPv4 exhaustion before it becomes irrelevant. On the other hand (as you said) trying this too quickly will just mean poor routability. From the draft: The Internet community can use network probing with any of several measurement-oriented platforms to investigate how usable these addresses are at any particular point in time, as well as to localize medium-to-large-scale routing problems. [...] Any network operator to whom such addresses are made available by a future allocation will have to examine the situation in detail to determine how well its interoperability requirements will be met. --- I now also see my comment above is quite negative. Don't get me wrong, the proposal seems technically neat and well researched. However I just don't see it as practical, and even if it was I wouldn't like it to happen and just delay the inevitable pain.