I have some comments on this.
There has never been a hardfork of Monero. We're still operating on the same blockchain that TFT started back in the day. The original Bitmonero software can still sorta connect to and sync to the network, although it will get stuck at certain times because the software originally evaluated block rewards incorrectly and couldn't handle tx_extra. So, unlike other blockchains like DOGE or DRK, we've had zero hardforks up to now (just softforks).
There are cases where the ByteCoin devs merged things in without review (seemingly), for instance a number of TFT's fixes. It's obvious that whoever owns the amjuarez ByteCoin repo trusts whatever TFT devs, which is unfortunate as he introduced a
very severe mining bug into ByteCoin (which Monero fixed a while ago).
The bug othe speaks of was first bypassed here:
https://github.com/monero-project/bitmonero/commit/5ceffa8c8abb96bb8314939bf75c9b935ea7b5bcI caught it originally when I added checkpoints to the code and noticed that the blocks before checkpoints weren't having their PoWs checked, This was very dangerous, because it allowed you to upload random blocks to anyone syncing the client that corrupted the block database. So, I disabled checkpoints and then fixed it properly.
https://github.com/monero-project/bitmonero/commit/3a3a8176782a4fa75b0607fba0393c9d4a1746be (blockchain_storage.cpp)
and checkpointing flagging was turned on here:
https://github.com/monero-project/bitmonero/commit/e7171250739790a5e5040264c4c1356ddeeea241BoolBerry has 100% the same code, so either they fixed it the same way independently or they used our fix. In either case, it was a very severe bug.