Yes, desperation to move the ball.
First, the HB pass was when it was 27-7 after several punts, sacks, etc.
Fake Jet was when down 7 in the second and is not a trick play by any stretch of the imagination (at least not for all the other FBS teams). Again beyond one or two plays no offense movement at all.
The flea-flicker was 7-7.
But, in all cases when he is having trouble moving the ball is the only time he tries this stuff. He could not move the ball passing or running and in desperation, he tends to resort to trick plays or wildcat.
Let's not pretend Perry moved the ball up and down the field. There was a big play here and there but three of the four TDs came after a penalty and turnover.