Hey Brian, glad to be of assistance.
You're correct the aluminum plate serves a couple purposes, supports the shoulder bells and helps prevent the yoke from cracking. At first I tried a simple reinforcement using left over scrap but quickly realized it wouldn't be enough so I created the bracket after getting a glimpse of some movie armor pictures. I've seen others do something similar but use plastic instead of metal. Not sure how those are holding up. I've either trooped or suited up over a dozen times and to this day I have no cracks
Anyway, hope this helps