I have a 45 degree irons.. I really can't say I have used it much. If something is so close that I don't use my scope, it is probably close enough that I can point shoot it. I am deliberating taking it off, though it isn't any noticeable added weight.
I like Taran Butler's method of shooting occluded with close in targets. He doesn't look through the scope for close in targets, he just makes sure the scope covers the target and blasts away.