2017-07-13 18:58 GMT-03:00 Dan Libby via bitcoin-dev <
bitcoin-dev@lists.linuxfoundation.org>:

> If I understand correctly, my node will accept the incoming tx inputs
> but obviously will not perform any segwit related validation, thus those
> inputs are not fully validated.  I don't yet understand how my node
> thinks they are valid at all given that it does not understand P2WPKH
> address format, so either it doesn't need to, or P2WPKH is somehow
> already valid.  I know this has all been discussed in the past, so if
> someone can point me towards a document that explains it I'd be happy to
> read that.
>

From your perspective, the P2WPKH will look like a anyone-can-spend
transaction, thus, valid no matter who is spending. So, you would be
basically leaving the security of segwit transactions to those who actually
are interested in and using them. If your fork becomes popular, it would
decrease the security of Segwit transactions to something akin to the
security model of the Drivechain currently being discussed: only those
particularly interested in that particular sidechain (and segwit witness
could be loosely categorized into a sidechain) will be responsible to
prevent others from stealing funds from the anyone-can-spend transactions.

-- 
Lucas Clemente Vella
lvella@gmail.com