I previously explored an extra state to require signalling before activation in an earlier draft of BIP8, but the overall impression I got was that gratuitous orphaning was undesirable, so I dropped it. I understand the motivation behind it (to ensure miners are upgraded), but it's also rather pointless when miners can just fake signal. A properly constructed soft fork is generally such that miners have to deliberately do something invalid - they cannot be tricked into it... and miners can always chose to do something invalid anyway.
-------- Original Message --------
From: luke@dashjr.org
To: bitcoin-dev@lists.linuxfoundation.org, shaolinfry <shaolinfry@protonmail.ch>
I"ve already opened a PR almost 2 weeks ago to do this and fix the other
issues BIP 9 has. https://github.com/bitcoin/bips/pull/550
It just needs your ACK to merge.
On Wednesday 05 July 2017 1:30:26 AM shaolinfry via bitcoin-dev wrote:
> Some people have criticized BIP9"s blocktime based thresholds arguing they
> are confusing (the first retarget after threshold). It is also vulnerable
> to miners fiddling with timestamps in a way that could prevent or delay
> activation - for example by only advancing the block timestamp by 1 second
> you would never meet the threshold (although this would come a the penalty
> of hiking the difficulty dramatically). On the other hand, the exact date
> of a height based thresholds is hard to predict a long time in advance due
> to difficulty fluctuations. However, there is certainty at a given block
> height and it"s easy to monitor. If there is sufficient interest, I would
> be happy to amend BIP8 to be height based. I originally omitted height
> based thresholds in the interests of simplicity of review - but now that
> the proposal has been widely reviewed it would be a trivial amendment.