Is teemo viable in rank?

He's very viable... in the right matchups. Never first-pick him. However, see the enemy top lock in or ? How about ? Get dat Teeto and make them wish they weren't melee.

To be completely honest with you any champion is viable if you understand them well enough.

There's Master/Challenger Teemo mains, a guy who got there playing exclusively Heimerdinger, Scrumm plays Talon only, and I mean to the degree that he plays him in the jungle as well as in the ADC position.

Yes he is, i went from unranked, did my 10 promos, won 8, loss 2 playing ONLY teemo, and made Gold IV on my alt, Wallymartss

He is a great objective controller, as well as a secondary point of harassment for the enemy jungle. Shroom up his red/ chickens, and he will be sad all game.

You are required knowledge of how to win a lane. If you cant zone the enemy perfectly out of the book. youre basically waiting the enemy to become stronger.

Only if you know what you're doing with him - as in: you counter-pick with him or you're just plain that good.