Currently listening to the History of Rome podcast. In the middle of the 2nd Punic War at present.
That there were 2 counsels and this setup worked kind of stuns me.
Sometimes it did and sometimes it... really didn’t. Polybius’ account of the Battle of Cannae is a good example of the latter (although beware authorial bias as per).
Specifically note that one of the Consuls who presided over that fiasco (the one who died) was the grandfather of Polybius' patron, and that filial piety may have resulted in a few cunning distortions here and there.