View in context in the libbitcoin Slack #general mirror.
database.turbo is configured (no parameter option)
The four legacy methods (using p2pkh and p2sh addresses as keys) are identical to the newer scripthash-based methods after address conversion (the sha256 hash of the output script is derivable from p2pkh/p2sh addresses). So the four older methods and newer methods each perform their own version validations and then just pass into common code for the bulk of the implementation.