There was one rather irritating moment when my Atlas C was fighting the Clan holed up in E5 and all my teammates where just hiding 200m behind me unwilling to move or even attack until after I ended up taking the base entirely on my own. 
The opposite was true on our team.
Once one guy moved towards or into a base, all the mechs in the area swarmed and took the base by force. It was like we moved as a school of fish with one mind.
A tactic that worked for me was to run straight through a group of big slow enemies with a Scat A popping off a few shots left and right. This made all the big mechs rotate so they were unable to focus fire on the base entrance where my teammates came behind. My teammates just moved in and took out all the IS mechs because they were facing the wrong way with their backs exposed to the brunt of our forces unable to defend themselves. I did this twice taking only medium damage because of my mobility and small profile.