Heavenly Sword Help Needed

[owa]

I'm trying to open a large gate after clearing a bridge (partially with a rocket launcher). I've gone to the right and to the left of the door (those paths) and got the bars withdrawn but it still doesn't open. I noticed that when throwing the shield to unlock an area (the really, really long throw) that it had the possibility of coming back toward me. So, I'm thinking that I need it to hit the target and come all the way back toward me to hit the one behind me. Problem is, I've tried that like a 1000 times and not got it. So, before I continue wasting lots of time trying that, I'd like to know if that is the correct solution.