I doubt wearing an outer ballistic shell over an inner shell is very practical in this day and age though. A throw back to the M1 helmet. Looks time consuming having to put both on.
If there's a threat your bucket is on. ;) Real or training, it's not to often any more that the troops don't wear them. I know the troops will figure out "quicker" ways to throw it on when they have to though. I think the overall ballistic protection will be greatly needed, I know a few friends that it may have prevented the loss of an eye or even worse.
True, I agree extra protection is always welcome. But for in order for it to work correctly, you will have to remember to put on both shells or try get the outer shell on too in time, particuraly if in a battle situation!?