That game was probably eye-opening for a lot of Steelers fans. I'm a Tua-guy so I have watched every Dolphins game for the last 3 years. McDaniel is legit. He uses a ton of run action (think play action except the OL run blocks with pulling guards, etc.) which freezes LBs and lets Tua hit the WR in stride over the middle. These are schemed up, easy throws that we don't do enough of. Also uses lots of motion and routinely goes for it on 3rd and 4th down, even from his side of the field.
Tua is a lot better than Kenny. In terms of processing, release speed, accuracy (Kenny's best attribute), manipulating defenders, and even arm talent (Tua's is average, Kenny probably a little below). But our scheme asks a lot of Kenny: tons of throws outside the hashes, WR in the same place, etc. We constantly put him in down and long situations through penalties and running on 2nd and long. He's just being asked to do a lot right now and that's not conducive to anyone, especially not a young QB on a medium talent offense.
I think Kenny can win a championship. He's very good against pressure (which is usually slow to develop) and stinks in a clean pocket. That can be cleaned up with more reps and film. His arm is good enough and he can escape pressure. Guys like Jimmy G have gotten close with good team talent and a friendly scheme. Tannehill has won a ton of games and he's not more talented than Kenny. No reason he can't ride a #1 or #2 seed with a good defense the way that Ben did in 2007.