Vanilla BurnBit required a public HTTP tracker. Experimental builds would integrate Tor onion services or I2P tunnels directly into the torrent creation wizard. You would generate a torrent where the "announce" URL is an .onion address, creating a darknet swarm invisible to standard internet surveillance.
If you are building or testing an experimental BurnBit-like tool, here is the core mechanism: burnbit experimental
The holy grail of experimental torrenting is Erasure Coding. Standard torrents fail if you lose specific pieces. Experimental BurnBit could generate a torrent where you only need 70 out of 100 pieces to reconstruct 100% of the data (similar to ZFS or RAID). Vanilla BurnBit required a public HTTP tracker