How did galley ramming tactics work?

How would galley tactics and ramming work in a battle such as Aegates?

A line kept friendly ships clear. Crews could ram obliquely to ease withdrawal, or damage enemy oars before closing to board.

A line presented the ships' rams towards the enemy while keeping friendly hulls clear of one another. Individual crews then sought an angle of attack on their nearest opponent. An oblique strike appears preferable in some accounts because it could open the hull while making withdrawal easier. Driving squarely into the enemy's broadside risked leaving the attacker stuck. To capture a ship, attackers could pull in their own oars, break the opponent's oars and close for boarding. Working the two sides' oars differently also helped turn a galley.