Date: Thu, 23 Jul 2015 05:39:20 +0000
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From: jl2012@xbt.hk
To: bitcoin-dev@lists.linuxfoundation.org
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Subject: Re: [bitcoin-dev] BIP 102 - kick the can down the road to 2MB
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Quoting Peter Todd via bitcoin-dev <bitcoin-dev@lists.linuxfoundation.org>:

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> Sorry, but I think you need to re-read my first message. What you've  
> written below has nothing to do with what I actually said re: how  
> you're BIP102 and associated pull-req doesn't measure miner consensus.
>
>

I think I have already answered this with my previous mail. If there  
is consensus among major exchanges and merchants, the preference of  
miners are not particularly relevant. A checkpoint could be  
implemented in a decentralized way to make sure miners of the original  
chain won't be able to overtake the new chain.

Bitcoin has no intrinsic value. Bitcoin has value because people are  
willing to exchange it with something really valuable (e.g. a pizza;  
or USD which could buy a pizza). If most bitcoin-accepting business  
agree to follow BIP102 and ONLY BIP102, then BIP102 is THE Bitcoin,  
and the original chain is just a dSHA256 alt-coin which one can't even  
merge mine with BIP102. Switching to BIP102 is the only economically  
viable choice for miners.

Having said that, a miner voting may still be useful. It is just to  
make sure enough miners are ready for the change, instead of measuring  
their consensus. For example, the new rule will be implemented 1) 1  
week after 70% of miners are ready; or 2) on 1 Feb 2016, whichever  
happens first.

For SPV wallets, they have to strengthen their security model after  
the BIP66 fork, anyway. They should be able to identify potential  
consensus fork in the network and stop accepting incoming txs when it  
is in doubt. My "version 0 flag block" proposal could be a good  
generic way to indicate a hardfork to SPV wallets. (see my previous  
email on this topic)