Currently and by Blizzard’s own admittance it is not the same Vanilla formula and doesn’t function the same
-many abilities that should be OFF the batching call -per Vanilla- feel like they are ON the batch
-abilities feel sluggish
-pets are unreliable, delayed and at times unresponsive
-abilities like Vanish or Feign Death do not drop combat instantly
-instant cast abilities like Counterspell Spell Lock, Lay on Hands, etc do not pop off instantly making timing difficult
-general interactions feel sluggish and unresponsive
-enemies can sometimes attack SECONDS after being CC’d while still CC’d in a stun/poly/fear - even at range if the enemy is a caster
-abilities execute and are put on CD but do not execute properly or at all sometimes
The list can go on but you get the idea.
You can still have a priority so 2 mages can sheep each other but the entire system bogs the game down and is causing more headaches than it is worth - often times resulting in being unable to pull of an ability when it SHOULD be off the batch.
Vanilla had it and classic should have it but since it’s not Vanilla’s system and, instead, deaigned to “feel” like batching - it is not accurate and definitely not reliable.
It needs to be fixed or removed. At no point from Vanilla through touring expansions has the game felt like I’m fighting against some artificial latency to play the game.
If it can’t work like it did in Vanilla then remove it, full stop. Right now it doesn’t and would probably cure a number of ailments from just a cursory glance at the bug forum. I believe many can be traced to this manufactured latency and batching system.