I love it on my Operative healer (lvl 24). You'd have to play more adaptive, you can't just sit your butt on a node, scream when people come then be dissapointed at your team.
Use your skills to heal them instead of solo guarding things and you'll win with pure muscle instead.
When I call out an inc Its not me that's defending I always keep my eyes on the other points as it bothers me when no one calls it out. I am not an idiot so I don't solo guard nodes as a healer I only do that on my main which is a tank.