I think some people don't quite understand how a long pass develops. It's not a matter of "The receiver is at location x, running with a velocity vector of V, with an acceleration that can be quantified (0, constant, or changing at a known/predictable rate, so I just have to throw it to location x_final, height h, at precisely time t." There are a LOT of variables that are constantly changing.
You have to throw the ball before the receiver even gets open ( most of the time), so you anticipate that they will get the separation, anticipate their speed/acceleration, their precise route, and the defenders technique. If ANY of those things change, it could throw off the play. Brady has no control over any of those things. A real deep-threat receiver adjusts to the ball, otherwise, there's practically no hope the play will ever work out right. It's just the physics of it. That's the problem right now. Brady has NO playmakers on the outside who have the speed/experience to make the right adjustments. Any real outside receiver makes that catch that Tymms couldn't reel in.
I'm not saying that Brady has a strong deep-ball game, but I think many people's criticism is completely unfair. Rodgers wouldn't fare much better if he didn't have Jordy Nelson to throw to...