Unknown, but seems unlikely. The hypothetical requires assumption of more SV mining power than ABC has displayed to date. It is certainly possible that ABC has also been mining a secret empty block SV chain as well. Hard to envision, however, where such hash power may have come from. ABC could also start later with greater hash, but that necessarily limits the depth of the potential reorg.
The 'centralized checkpoint' is an interesting twist as well. How much economic weight is running code incorporating this feature?
I was actually kind of surprised that the massive redirect from BTC to ABC came from Bitcoin.com. I had envisioned it coming from Bitmain. Perhaps Bitmain's hands are tied due to the pending IPO?
No, I don't think their hands are tied at all. That's another of Wright's ridiculous statements. Bitmain has a HUGE investment in BCH assets. Not only they can, as a business, do whatever deemed necessary to protect that investment but they are compelled to. As long as you can reasonably justify (even if wrong in the end) the decision it is ok from a corporate/shareholders perspective.
Also, not only Antpool has joined the party directly but we don't know if they have redirected some of their hash to Bitcoin.com pool. Also, we don't know if they are contributing to some of Bitcoin.com expenses on loses (compensation that could be in BTC, BCH, USD or even free machines and/or future discounts).
To me there is not much difference using "owned" vs rented hash... in the end it is all a cost you are willing to assume. And in none of both cases it implies a long term commitment, as you are equally losing money for spending the hash in loss until you can't or don't want anymore.
It is hard to guess where additional hashpower could come from for SV, but it is not hard at all to guess multiple sources where hashpower can come from for ABC:
- From their actual KNOWN hashpower currently mining BTC and other SHA256 coins.
- From newly produced not yet sold machines. They could even sell them on discount to other miners in exchange of mining deals of ABC.
The thing is, BCH was a minority chain of BTC. Satoshi already warned about the most probable fate of any minority chain. For some reason, it has been artificially allowed to coexist along BTC besides sharing the same PoW algo where BTC is king. That was always risky for reasons now evident.
About the checkpoints... I think all exchanges are using it, what I don't know is how frequent the checkpoint is. If it were me, I would set a checkpoint with a frequency higher than the minimum confirmation requirement to avoid double spends (which is probably the biggest fear of exchanges).