There's still tricks to getting around the zone with only having to clear the trash in each of the boss rooms or adjacent rooms. I'm assuming they only added the DT mechanic to the bosses and not the trash.
Obviously everyone knows how you just walk to Aten's room so I'm assuming because of that, everyone should know you can drop your entire raid inside a wall in mini aten's room and walk in to the room when ready (there's a corner you can fight him in that will not aggro any trash) and also you can drop in to the west blob room and walk to the very back wall and fight him with your entire raid in that cubby without aggro'ing trash.
For the rest of the bosses, you just use the two mage coth/rewind trick to get to an adjacent room and coth your raid in. Can do this for all the rest of the bosses except north/south blob. You just bring a group of monks or a normal group with an evac to the location that you want to mage bolt a non-see invis trash mob to. Mage bolt a trash mob from a room you want to get to, it warps to you, have the monks or group you brought take the mob down to 40-50% health and then FD or evac. The regen in VT is insanely slow, takes like 30 minutes for the mob to regen back to 100%. The mob will go back to his room once aggro has been dropped. You then start a bolt on the low health mob on mage #1, while starting a coth with mage #2 on mage #1. The bolt hits, mage #1 gets summoned, then immediately cothed back. Mage #1 casts invis then does a /rewind, moves to a corner and then starts cothing raid in.
With some practice this takes maybe 15 minutes total for setup/execution/cothing entire raid in. I've done this before for every VT boss that you can't run to, except north/south blob. You'll only have to clear the trash inside the actual boss room or fight him in a spot where you can bypass most of the trash in the room.