On Thu, Feb 04, 2016 at 12:36:06PM -0500, Gavin Andresen via bitcoin-dev wrote:
> This BIP is unnecessary, in my opinion.
> 
> I'm going to take issue with items (2) and (3) that are the motivation for
> this BIP:
> 
> " 2. Full nodes and SPV nodes following original consensus rules may not be
> aware of the deployment of a hardfork. They may stick to an
> economic-minority fork and unknowingly accept devalued legacy tokens."
> 
> If a hardfork is deployed by increasing the version number in blocks (as is
> done for soft forks), then there is no risk-- Full and SPV nodes should
> notice that they are seeing up-version blocks and warn the user that they
> are using obsolete software.

1) There is no way to guarantee that nodes will see those blocks, and
the current network behavior works against such guarantees even in the
non-adversarial case.

2) I know of no currently deployed SPV wallet software that warns users
about unknown block versions anyway.

-- 
https://petertodd.org 'peter'[:-1]@petertodd.org
000000000000000008320874843f282f554aa2436290642fcfa81e5a01d78698