On Sun, Dec 20, 2015 at 11:35 AM, Peter Todd <pete@petertodd.org> wrote:

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On 20 December 2015 08:30:45 GMT-08:00, Chris Pacia <ctpacia@gmail.com> wrote:
>On Dec 20, 2015 6:34 AM, "Jeff Garzik via bitcoin-dev" <
>bitcoin-dev@lists.linuxfoundation.org> wrote:
>
>> 2) This reverses the useful minimization attribute of HD wallets -
>"just
>backup the seed"
>
>It would be nice if the bip37 filter matching algorithm was extended to
>serve up the proof.
>
>And if server-based wallets did the same it would preserve the "just
>backup
>the seed" functionality.

Exactly! The information will be out there - "just backup the seed" requires someone to have the exact same data needed to generate the TXO-unspent proof that my proposal requires to spend an old txout.

tl;dr: jgarzik is incorrect; theres no difference at all from the status quo.

The data stored in the legacy case makes it possible to sign and send a transaction without any connection to a network. The data stored in the upgraded case, absent grandfathering, requires significant network sync at a minimum.

The user experience and security parameters are different.

Thus, issue/recommendation #1.