Seriously noobs, you're on 5% health, you're against 3 other players on your own, no where near any of your team mates
DERP HURURRR FORCE BARRIER U CANT HIT ME IM IN A FORCE BARRIER DERP DERP DREP
The funny thing is when the 3 people pause and stand there ready to use their execute ability.
I'm a pure dps sentinel -- But IMO the best use of force barrier at this point is poping it early on, like right when you start getting focused -- Or simply delaying a node cap.
EDIT: However, multiple sages/sorcs on comms coordinating their barriers can be quite devestating to the progress of the enemy team.