Enmity no. Provoke yes. For five seconds (two attacks) you can only TARGET/LOCK ON the tank that voked you. You can still place AoE, still damage with AoE, and still run away. This still allows tank's to be as disruptive as they already are, and it puts a very minor limit on what you can do.

Uses:
Saving a party member
Interrupting a capture
Disrupting Raw Destruction
Disrupting enemy heals
Forcing attacks on your more sturdy self

What it can't do:
Prevent you from using weaponskills or abilities
Prevent Cometeor or collateral damage from the ranged LB
Prevent Asylum, Sacred Soil, or similar abilities
Prevent the spread of SMN Dots
Prevent BLM aoe

It would be a tactical tool almost as annoying as stun or sleep, but with more options to the victim.