If your aiming to have the equip go on at the same time as the ability goes off, your landing a risk of the connection laging (Which happens alot during peak hours or heavy conjestion of players/mobs) and the server reading the equipment for melee/enhancing set being equiped too late or too early.
however you need to make sure your still equiped at that time since it could take anywhere between 1-2 seconds for the ability to go off dependant on lag (Even if .5 is enough, 1 second plays it more safely). its as I said before, they changed wyvern breath attacks to fire off at 1.25 or 1.5 (I forgot which) instead of 1 second since the server wasn't registering on time because of peoples connection.

The server is precise, its our computers/connections/other factors that aren't reliable