I've heard that this desync issue has been going on for a long while, but it has become a problem for me since GU3. After an indeterminate period of time in game, I will no longer cause any damage what-so-ever. People still have no problem shooting me.
I don't think they'll fix it. They expect you to fix it. It's related to CPU and MB settings. Turning off my monitor/sensor worked for me.
