I think I did that once and that was when I wanted to record a clip of the game and needed sunlight.
Is it just me or should Drew start using first person aiming more? I do most of my shooting in first person. Unless enemies are right in front of me I always go first person mode. I find it much easier to line up your shot and take bullet drop into account and whatnot.
Yeah I'm surprised he's found as much success as he has - I use the first person mode almost exclusively for the pistol and can't hit anything without it.