I just wonder whether TJack's shaken confidence passes on to his receivers.
Now I'm a very weak catcher, it's not my speciality to say the least. But even if you are a good catcher... you have to be able to trust your QB to put the ball right on the money. You run your route, you find some space, you turn towards the ball at the last second... as a receiver you have to trust that when you make that turn that ball will be right on you, or at least be catchable.
So in this respect, I don't think it's TJack's throws missing a mile wide that are the biggest problem with regards to the mental status of the receivers. It's his inconsistency... it's those balls that drop just beyond the gloves when the team are trying for a big play. If the receivers are out running their routes and they have any doubt about TJack's ability to put the ball on them, they'll come out less intense and may even start missing the ones that are catchable
Note: I'm not making excuses for receivers missing catches, if you get a shot it's up to you to take it. But I'm just pointing out that the receivers and QB play as a unit, the mental status/play ability of one will be affecting the mental status/play ability of the other.