Exactly. Well said. I'll add my two cents.
1) What is the average yardage required to attain a first down on 2nd and 3rd down forTannehill vs Brady?
2) What relationship, if any, is there between down and distance with YPA or QB rating?
Tannehill, with his lousy OL and running game, I assume had among the highest average yards required to attain a 1st down on either 2nd or 3rd down. While Brady is typically facing 3rd and 3, Tannehill is typically facing 3rd and 9.
Suppose a QB faces a lot of 3rd and longs. One QB might be prone to attempt to complete a more difficult pass in order to pick up the first down, to the detriment of his YPA and QB rating, because he is concerned with winning as opposed to protecting his statistical measurables. Another QB might decide to throw a safe underneath pass which, while elevating his YPA and QB rating, fails to pick up the 1st down. Would this be winning football? Is this the mark of being a better QB? Maybe. Maybe not. What yard line are you on? What is the score of the game? How much time is remaining?
So to say that a QB's OL play and running game have no impact on a QB's YPA or QB rating is ludicrous. These statistics are dramatically influenced by both down and distance as well as field position and the score of the game. If it's 3rd and 20 and you're winning a QB can throw a safe completion that the defense gives you, thereby augmenting your statistics; conversely, if it's 3rd and 20 and you're losing, you are obliged to incur more risk which has a greater chance of lowering your statistics.
Conversely, when it's 3rd and 3 and you have a good running game that QB also benefits from the defense not knowing whether to play the run or the pass. Here again, Tannehill is at a distinct disadvantage as compared with Brady, irrespective of talent, as the defense will most likely play the pass given the futility of the Dolphins' running game. Against Brady on 3rd and 3, the likelihood of either a run or a pass is nearly equal.
Bottom line is that it's a team game and the team's success in other phases of play dramatically affect the situations which allow a QB to improve upon his individual statistics,
even when the underlying talent of two QB's under comparison is equal. And I would argue that these situational variations caused by the team's performance excluding the QB are too complicated to be controlled for when presenting basic statistical comparisons and analyses.
Because the assumption is that the only difference between NE (the division winner) and Miami is Brady vs Tannehill. That is delusional. WE WERE THE WORST PASS BLOCKING LINE IN THE LEAGUE AND THE 26TH RANKED RUSHING TEAM. Why the hell to posters on this message board keep ignoring the fact that this team had serious issues that are unrelated to the QB?