So I had an idea and after testing can confirm it works, what you do is make an equipment set with 4 piece t12 on and equip it(I don't recommend using your normal PVE set because your pvp trinket will get a cooldown from swapping). wait until about 3 seconds before the gate opens and cast Tricks of the Trade on your partner then click your full PVP item set. the gate will open and you'll have about 27 seconds of either 25% more haste, crit or mastery. admittedly not game breaking, but everything helps! Hope it helps, enjoy!