On dictonary attack, when the flipper found a key on a bank, it doesn’t check directly this key on the other bank.
The process start at the beginning on each bank.
Reuse found key will increase efficiency of the dictonary attack.
Also check each key on all bank will increase efficiency too :
key 1 → bank 0-15
key 2 → bank 0-15
etc …
key n → bank 0-15