Here we are. Bitcoin Cash is divided for its leaders aren't willing to act in concert anymore. Probably for quite a while already. It only became apparent when one side unilaterally announced changes which the other side had previously already rejected. But the messenger is not by default the one culpable for the relationship split. One can get a sense of this separation being mutually desired when watching e.g. BU Podcast - BU Lead Developer & His Vision for BCH (mark 25:00): "We lost three years [with ABC in the lead]". There are obviously other issues besides the IFP debate. In terms of development it will be most effective if everyone follows their vision and ideals.
What is true for the development is not necessarily true for Bitcoin Cash gaining adoption. Any further splitting could potentially set us back. If the split continues hostile the following fighting can unnecessarily set us back for years yet again. If the split were amicable it could even be beneficial [1,2]. The latter is true but comes with two challenges attached, the ticker and network security.
Ticker Symbol
Some people claim a ticker is not important because the success of a project won't depend on it. But the argument denies the nature of cryptocurrencies. They are not purely technical but social at heart. A technical implementation without adoption doesn't make a currency. It is by no means set in stone that the technically best currency will be the most successful in the long run. Political, technological, societal, and market forces act intertwined and the ticker represents it all.
Interestingly this is where the two sides of the debate differ in their views. The supporters of Bitcoin ABC seem to agree by and large that the current adoption level is insignificant and any first real-world blockchain business solution will attract orders of magnitude larger user bases than currently seen. The supporters of the No-IFP side highly value the gained community and adoption and believe that it is the actual backbone of the currency which will propel adoption. Currency adoption by business development versus currency adoption by integration of existing businesses.
Network Security
No side in this debate has any interest in losing shares of its network security. Bitcoin Cash is already just barely out of the mercy of miners from the stronger SHA256 chain. On first sight it seems best for both sides to try to accumulate as much support as possible prior to the hardfork. The best outcome is often claimed to outcompete the other side and hinder its creation (if ABC gathers too little hashpower their chain will also be wiped out).
Given the current prospect of divide in community and miner sentiment (see initial charts above this text) it is unlikely that any of the resulting chains would be significantly lower valued than they currently are (Coinflex is a bad reference due to too little liquidity). Either users sell their less liked fork token to get more of the beloved one (leaving values identical if number of user on both forks are similar) or users simply hold onto both (leaving values identical).
At a second glance thus Bitcoin Cash might actually become stronger with the existence of a NoIFP and an IFP fork. Especially so when compared to the network security of Bitcoin Core. It's proven time and again that competing forks have larger marketcapitalisations combined just after the split than their basechain had before. Since hashpower follows price (there's profit to be made), their combined SHA256 hashrate will represent a larger share of the total pool of all SHA256 blockchains.
Solution: Amicable Split
To avoid further community infighting, a long and severe hashwar with bad PR and uncertainty, let's make this beneficial and wish each other's projects well - paving the way into cooperation (@trout has a great take on it on twitter). So here's a surprisingly simple, yet maybe naive solution. All it takes is the following:
Both sides announce a new ticker (e.g. Bitcoin Cash XBC and Bitcoin Cash ABC).
Both sides announce amity and implement replay protection. Despite code freeze there would be time for this.
Nobody wants to give up the BCH ticker and the Bitcoin Cash name. This is not gonna happen. Only the loser (probably ABC) will have to choose a new ticker and name.
Opt-in replay protection would be useful, e.g., an OP_RETURN string momentarily forbidden in the protocol.
Mandatory replay protection (e.g., different SIGHASH) is terrible for wallets and applications.