Using your own logic, Mankins did not struggle in the Week 17 contest. Why? Because the Pats did not have to shift protection to the right side throughout that game. When you combine that with the fact that the quick passing game was working, you get the result of the Week 17 game. Further, as has been mentioned, Brady was still pressured more than he was in most games that season during that contest. In the Super Bowl, the Giants adjusted their coverage in the back end and that, along with the loss of Neal after the first series (again, one which they marched down the field for the score) and a gimpy Brady lead to unrelenting pressure. So yes, in other words, injuries were a very important reason to that loss. Much more important than you're making them out to be.
Where did I do that? This is another red herring. There were plenty of factors for that loss. There are usually a number of factors that take place in any game to determine a winner and a loser. Injuries were a huge reason for it as well, as has been pointed out to you.
That's certainly one reason the Seahawks lost that game. So yes, I would agree there. The question is whether or not Edelman would have still had the game he did with Lane in there but there is no question that his injury opened things up. The minute Simon came into the game, Brady told McDaniels that's where they were going with the ball and the results spoke for themselves. So, once again, you make a point that injuries were a huge part of that contest as well.