SaK requires you to plan out your attack, and try to avoid the clusters.
As a good player, it is better for you and your squad to not engage in a massive fire fight at heavily contested zones, but rather use buildings and covers to sneak around and take flag from flag, and run away.
Standing up and fighting the massive crowd that is angry to kill you is pretty suicidal, as you can get overrun pretty easily in that map.
The strategies I used, though with tweaks due to destruction and new enter-able buildings, in the past still works great.