Create more single player lockouts...

[Teleniel]

You can tank swap without Provoke, but you have to be on the ball with your enmity gain and make sure you are JUST behind the other player. They will have to stop building enmity (cast Stoneskin ... go for debuff combo rotations etc.) if you watch your enmity right it takes 1-2 actions without provoke... 10s tops (5 actions)

[Tyrial]

You can tank swap without Provoke, but you have to be on the ball with your enmity gain and make sure you are JUST behind the other player. They will have to stop building enmity (cast Stoneskin ... go for debuff combo rotations etc.) if you watch your enmity right it takes 1-2 actions without provoke... 10s tops (5 actions)

And your average player who actually takes their class/job seriously takes the time to get their important cross class skills before they attempt anything that's more difficult than your average story progression. If this guy couldn't be bothered leveling his Gladiator to 22 for Provoke then I highly doubt he's going to be competent enough to ride the other tanks' aggro to the point where he could easily pull it off him before he hit 5 stacks.