M855A1 Performance Review. Did it live up to the Army's hype? Did going green really work?

Touted by the Army as a more accurate and lethal bullet than the older M855 "Green Tip". But is this really true? Did going green with a lead-free design really work? Does it damage M4 carbines? Here I take a deep dive into the performance of M855A1 ammo, based off my time using it in Special Forces and my own accuracy testing.
Defensereview.com articles:
https://defensereview.com/m855a1-penetrator-ammo-accuracy-how-good-is-it-really/
https://defensereview.com/m855a1-5-56mm-nato-penetrator-ammo-feed-ramp-issues-real-hype-or-just-overblown/
Anniston Army 5inch standards:
https://www.youtube.com/watch?v=2zx3pzlexjE&t=240s
M855A1 used at a match
https://www.youtube.com/watch?v=yVZJ-DEKNR0&t=8s
Practical Accuracy Interview NGSW
https://www.youtube.com/watch?v=urEKLym1LGw&t=615s