Master Yi in dominion
 

He's going to be very viable.

please explain how, in my opnion he is only good for backdoor.

Ulti, get to any point instantly

Tf and panth cant do that?

Assuming they get banned yi would be a good choice

If Yi is a good choice for that reason alone, Zilean and Janna are better.

Not neccessarily. Although they too have high mobility..upon reaching a control node Yi will be far more successful than either Zilean or Janna at actually killing an enemy guarding it. It really depends on what the circumstances are upon reaching that particular node.

eve invis and ulti

If you use your ulti to run to the area (like a freaking moron), then you won't be killing anyone upon reaching it (since your ulti is down, and you are total trash without your ulti).

assuming yi is banned, tf and panth would be a good choice

you can't asssume someone will be good based on assumed bans, you know nothing about it right now, you can't say tf and panth will always be banned