I'm still not quite clear on the purpose behind the squads... what is it?
My gt is: XxIAmLegendxX
you can spawn on your sqaudmates. A balanced squad allows you to hold a position for a while. Once some of the people "trying out" the game die down, you'll see it better in action.
Another reason is, it's VERY hard to penetrate an area as just 1 person without taking the long way around on your own. Getting spotted once can screw you over. As a squad, you can focus fire. That's why you get suppression bonus, assists, etc. It's telling you to do more than just kill.
It's really a hard dynamic to explain unless you truly experience the glory of it. That's why BF3 is not a game for everyone too. A lot of people prefer being lonewolves ala COD style so they can claim they're the best.