I also think it's reasonable to assume that a chain split does not mean a market cap split, given that we didn't see this when Ethereum split into Ethereum+Ethe

I also think it's reasonable to assume that a chain split does not mean a market cap split, given that we didn't see this when Ethereum split into Ethereum+Ethereum Classic. In my opinion, market cap is too superficial to capture what happens in the market. A better measure would be market depth: how many coins can you sell into the market before the price goes to zero? This figure very well might split into two, since otherwise it would require action on part of the market makers, i.e. entering the BCC/USD or BCC/BTC market.