Trust me when I say this, players usually meet expectations. Let me explain.
If a Coach goes for it on 4th down in a pressure situation the team will always love it. Why? Because they see it as a vote of confidence. If a team is allowed to play sandlot football (hope that description doesn't make anyone misunderstand) they get the same vibe.
If however, the Coach is always conservative, the team does get the idea that he fears them screwing up in a crucial situation.
Consider it a self fulfilling prophecy. It's like the parent who has a kid at the dinner table. If you tell the kid "don't spill your milk," they spill it. Keep your mouth shut and they don't spill the milk. It's like you put the idea there so it makes it more likely to happen.
Parcells is a master at the psyche game. The question is, can he use that to psyche the other team? No doubt he gets results from his players with it. The trick is to get in the heads of the other team.
I think Martz (your example) does that. Teams are always wary of the deep throw and that means they are on their heels and big plays beat them. Even if it happens in front of the defender because in trying to recover they are out of position.