4-time deployer here (2x OIF, 2x OEF). Never saw anyone using the elbow pads and never used them myself when going on patrol. My second deployment the unit made them mandatory (4th BCT, 3rd ID) starting with the trainup, and we still ditched them almost immediately as soon as we got to the range. They stopped trying to enforce it pretty quickly.
They were bad for circulation, especially in the heat, and made it harder to shoot from any supported position. Never had to "dive for cover" while wearing them. Just an extra piece of gear that was more trouble than it was worth.
I was in OIF 1 (April 2003-March 2004) and didn't downvote you so...
ETA: 4 ID, including supporting 4-42 FA when we pulled security for the high speed guys when they caught Saddam in Ad Dawr in December