Using OP_CHECKDATASIG
What is the upcoming BCH hardfork all about?
Some controversy
There are actually two new, so called, OP-Codes added to the Bitcoin Cash ABC {BCH} version. And that is what caused quite a stir in the Bitcoin Cash realm. Where the Bitcoin Cash SV {BSV} version is in the opposition part. There is a claim that no re-activation of some Bitcoin software functions are needed. And if Bitcoin Cash ABC does move forward with the planned hardfork of the 15th of november 2018, Bitcoin Cash SV {Satoshi's Vision} will take over the BCH blockchain.
Simply stated, if the new CHECKDATASIG OP-Codes {Operation Codes} are added to the Bitcoin Cash ABC {BCH} Scrypt list, then Bitcoin Cash SV {BSV} will go and mine for the longest chain, with the highest accumulated hashing power. That means 'war' in the Bitcoin Cash realm. Hard to imagine there is not going to be some kind of replay protection to be build in. As it would be quite easy to distinct between the two main rivals, thanks to the new OP-Codes.
The BSV nodes will most probably refuse any transaction that contains OP_CHECKDATASIG / OP_CHECKDATASIGVERIFY operations. As 'it' does not 'know' what to do with them. So, while these OP-Codes get activited on november the 15th 2018 on the BCH blockchain, it is quite doubtfull if it is getting used right away. The first '_battle _', I expect, will be about which version of Bitcoin Cash gets control over the current BCH blockchain. Miners and full nodes will have settled this within a few days after the hardfork, I think.
The original Bitcoin Team
Basicly there is a bigger struggle going on below the surface. As I think the team that was known as 'Nakamoto Satoshi' (surname put last) did innitially consist of people like Craig Wright and Adam Back. Can you imagine them both as captains on the same boat? The team member posting on the BitcoinTalk I suspect to have been Adam Back. As Craigh Wright would have given away his identity in a jiffy, right after his first: "Fog off!" His communication skills are a tad bit like: "I dictate and you fogging swallow it down as the only truth. Now say you agree!"
Even if there would have been other team members in this Nakamoto Satoshi group, they would have failed to keep it together. So, at some point they split up, keeping silent about it. Each ging into their own direction. Different ideas about how Bitcoin could be used as sound money. Having 7 billion humans, many goverments and a lot of banks and companies use it would need more than 7 transactions per second. At this point in time the base for the future split of Bitcoin was already build.
Two main Bitcoin companies
Blockstream with Adam Back at the helm and Nchain with Craig Wright as the captain, the two main Bitcoin rivals. And somehow Roger Ver got stuck somewhere in the middle. There is an apparant completely different approach Wright and Back have towards 'their' shared invention. Some might be under the impression it is just about scaling Bitcoin. You know that 'big blocks' thing some Bitcoin maximalists and fundamentalists still fight about.
But I have come to a different conclussion. It is in the approach to what Bitcoin in its essence should be. Here you can witness Craig 'professor' Wright promoting the intregration of Bitcoin in the excistent Banking Monetary Governance {BMG} system. While Adam 'cypherpunk' Back apparantly is on the voluntarist side of the chain, where Bitcoin is to be used a free and open substantive system. If these two men ever had teamed up as 'Nakamoto Satoshi' it sure was not ment to last.
The system in, or out?
One thing I respect Craig Wright for is that he made his point of view very clear, from the very first moment he got out of the "I am Satoshi Nakamoto" closet. Bitcoin was going to be sound money that would be legal in every country in the world. And this would mean it had to fit in perfectly within the Banking Monetary Governance system. Up to a point where TeraByte {TB} blocks would need for Bitcoin to have a suitable infrastructure. And this could only be provided by...: The (Banking Monetary Governance) System.
Now, Craig Wright has been open en direct about his ideas and goals. Therefore I am, up to this day, very unpleasently surprised by some anarco capitalists, libertarians and voluntarists cheer for this blunt and rude marxisto capitalist. (Marxist Capitalism: A self acclaimed elite, an oligarchy of capitalist, ruling over the masses, with the Banking Monetary Governance {BMG} system.) He is intertwined with the system and he will explain it as such!
OP_CHECKDATASIG is illegal?
At least that is mainly the claim that Craig Wright is making. Followed by a lot of threats that he will take anybody to court who supports the Bitcoin Cash ABC 'OP_CHECKDATASIG' hardfork of november the 15th 2018. Maybe you can understand now where his aggression might come from. According to him adding'OP_CHECKDATASIG' will make Bitcoin Cash_ {BCH} illegal to use. Which would basicly destroy the usage for Bitcoin Cash as it should be in his vision. As an intregrated part of 'the system' and as such controled by it.
With OP_CHECKDATASIG activated for BCH it could become programmable money. Where scripts could use external data to have conditional payments settled. That could be claimed afterwards or even get returned if no claim was made. Imagine Bitcoin Cash being send to an email address, or any kind of social media account, for instance, that would surely change things for BCH big time, I think. And on chain gambling might be a part of the OP_CHECKDATASIG usage, like betting on binary options.
Even lightning network?
Well as irony seems to be connected to anything Bitcoin related I now do smile. Using an external witness to proof some data on the BCH blockchain does ring a bell for me. Being able to do off chain financial settlements that can possibly quite anonymous, well somehow just gave me a insight lightflash. Do I mind how the developement of Bitcoin Cash (ABC) and Bitcoin are showing the same kind of solutions? No, I will still use BTC, as the Bitcoin I prefer.
It is my guess though that this is now where it all boils down too. The reason Craig Wright and Nchain constructed their own Bitcoin Cash, Satoshi's Vision, {BSV} version is purely to keep it on track. And this track is layed out towards the Banking Monetary Governance system. Just watch his presentations, it is hard to deny that he is very open and honest about it.
Roger Ver might have known
The enemy within, that is actually Craig Wright and Nchain wanting Bitcoin Cash Satoshi's Vision to become an intregrated part of 'the system'. And for this it has to meet legal standards, which totaly oppose the ideals of anarcho capitalists, libertarians and voluntarists. That is the biggest 'battle' that will be fought. Cryptos as an alternative to '_the (Banking Monetary Governance) system, or being integrated and centrally controled by it.
And I can understand how Roger Ver must have been in denial, as there are many who still are. Good things still can happen though, for Bitcoin Cash {BCH}, for Bitcoin {BTC} and all the other Cryptos out there. So, it is not that I have suddently swapped sides, yet I see the importance for Cryptos, to be a future substantive system, coming forth from this Bitcoin Cash_war_. Therefore I state:
"May OP_CHECKDATASIG win!"
Is the end of a decentralized free Bitcoin near?

Image license CC0, source Pixabay.
Interesting _OP_CHECKDATASIG sources
https://nchain.com/en/blog/rabin-signatures-bitcoin-cash/
https://github.com/BitcoinUnlimited/BitcoinUnlimited/blob/bucash1.3.0.0/doc/opdatasigverify.md
https://www.yours.org/content/the-story-of-op_checkdatasig-f79679d52b23
https://lists.gnupg.org/pipermail/gnupg-devel/2014-January/028147.html
https://github.com/Bitcoin-ABC/bitcoin-abc/blob/master/src/script/script.h
https://www.reddit.com/r/btc/comments/9bpp8z/using_pgp_signatures_with_bitcoin_script_op/?utm_source=amp&utm_medium=comment_list
https://gist.github.com/ClemensLey/5fdec17f84142fe5b06e3171f907503b
https://github.com/bitcoincashorg/bitcoincash.org/blob/master/spec/op_checkdatasig.md
https://gist.github.com/markblundeberg/af59d7cd234cbdb14dcf9e00f0ea2c17
That should keep you reading for a while.