Again its not a graphical lag issue (so it doesn't matter your machine's specs or your graphic card). Its NOT from Helltooth WD visible spell effects (altho the fire is annoyingly to bright an orange--no one can see Desecration effects for example).
Rather is network LAG spikes that happen when the WD lays down multiple Walls of Death. It will bring a GR to a stand still for 10-45 seconds. Frozen. And then it catches up and most melee are dead. And the timer bar on the GR leaps forward. It sucks.
Its all the underlying math formula client-server calculations for damage, etc. crashing the group's latency.
If you add a Monk Palming everything to the mix -- on medium-large GR trash packs - you can go get a sandwich and drink and come back and the game will still be frozen solid.
It needs to be fixed ASAP. I cannot believe months of PTR testing and Blizzard didn't fix this.