I think I can help narrow this down after some thought. I think this is an issue facing all of multiplayer on the NA servers. I forgot the developers aren't from NA and that would make sense why they haven't seen this issue. It most definitely started around 4/24 so maybe its something to do with the NA server providers that was changed on that date. The performance of registry was far far better before whatever happened around 4/24. So I'm guessing it has to do with something that was changed to the NA servers then and not the update itself. The same thing that happens in the video of throwing weapons hitting then shifting and registering as hits in another body part happens ALL THE TIME. They go through enemies/horses or they hit and shift to a different spot. Obviously the client and the server aren't passing information as well as they use to prior to 4/24 and its showing up as these weird missing/registry hits. It happens with all attacks but its clearly most obvious with throwing weapons. I've had many times where it passes through entire giant sections of horses and misses and even through stationary players right dead center. It's not ping related (always under 40 ping) and it happens to everyone on the NA servers since 4/24. It was so apparent that I noticed it right away on that day because I play multiplayer often. Digi's video there isn't the best showcase of it no offense, I've just seen really blatant weapons flying through enemies that never use to happen before after last weeks changes.
I really hope you guys can pinpoint this because multiplayer registry was running very well leading up to 4/23. My guess is the issue is in the NA servers.